Version 4.0.2  (2020-10-03):
	* Fix typedef Function in cint_funcs.h
Version 4.0.1  (2020-10-02):
	* Update docs
Version 4.0.0  (2020-09-23):
	* API Change. PTR_LIGHT_SPEED is replaced with PTR_EXPCUTOFF.
	  Integral screening parameter can be passed through env[PTR_EXPCUTOFF]
	* Add short-range integrals for range-separation
	* Handle linear dependency in Rys polynomial
	* Avoid calling exit function (issue #41)
Version 3.1.1  (2020-08-25):
	* Fix bug in (py, pz, px) order
Version 3.1.0  (2020-08-25):
	* Add convention py, pz, px
Version 3.0.20  (2020-05-13):
	* Fix integral ggkin
Version 3.0.19  (2019-11-30):
	* support fractional nuclear charges
Version 3.0.18  (2019-07-02):
	* Fix undefined varialbe in nabla-rinv integral
	* Add integral < i | nabla-rinv | j >
Version 3.0.17  (2019-04-29):
	* 3c2e and 2c2e integrals for Gaussian type geminals
Version 3.0.16  (2019-03-23):
	* New 2nd order 3c2e integral ( i j | nabla nabla k )
Version 3.0.15  (2019-03-18):
	* F12 second derivatives
	* Add integrals for Gaussian type geminals
	* Add 4th order derivatives of 2e integrals
Version 3.0.14  (2018-11-22):
	* F12 derivative integrals
	* New 2c2e integral ( nabla nabla i | j )
Version 3.0.13  (2018-06-11):
	* New integral < | r r r r | >
Version 3.0.12  (2018-05-01):
	* New integrals < sigma dot p i | r | sigma dot p j >
	* Fix the undefined int64_t type in Fortran interface
Version 3.0.11  (2018-03-23):
	* Fix breit integrals
Version 3.0.10  (2018-03-20):
	* New integrals
	  <i | r p | j>,
	  <i | r r p | j>,
	  <i | r p r | j> and
	  <i | r r r | j>
Version 3.0.9  (2018-03-08):
	* New integrals (i |nabla j) and  -1/2 *(i | nabla^2 j)
Version 3.0.8  (2018-02-14):
	* Fix Fortran APIs
Version 3.0.7  (2018-01-15):
	* Add 3-center SOC integrals
Version 3.0.6  (2017-12-20):
	* Add integrals for X2C graidents and hessian
Version 3.0.5  (2017-12-11):
	* Use cmake policy for OSX rpath
Version 3.0.4  (2017-10-07):
	* Update tests to pass ppc64 architecture
Version 3.0.3  (2017-10-04):
	* Fix the long double precision issue in rys_roots for armv7
Version 3.0.2  (2017-10-02):
	* Update root-finding code in rys_roots
Version 3.0.1  (2017-09-27):
	* Fix typo in rys_roots output message
Version 3.0.0  (2017-09-20):
	* Change github master branch to the 3.0 version


Version 2.8.17 (2017-06-29):
	* Second order derivatives for 3-center 2-electron integrals

Version 2.8.16 (2017-06-02):
	* Add 4-center 1-electron overlap integral
	* Add Breit-type integral p1 dot r12 (1/r12^3) r12 dot p2
	* Fix code generator to handle (1/r12^3)

Version 2.8.15 (2017-05-22):
	* Improved R_qnode convergence

Version 2.8.14 (2017-05-18):
	* Fix cint3c2e bug for general contraction on auxiliary basis

Version 2.8.13 (2017-05-13):
	* Bugfix for range-separated ssss type integral;
	* Bugfix for quad-prec gamma_inc function in rys_roots.

Version 2.8.12 (2017-03-07):
	* New 2e integral (ij|pk dot pl)

Version 2.8.11 (2017-03-06):
	* New 1e integral <pi |Vnuc| dot pj>

Version 2.8.10 (2017-02-22):
	* New 2e integrals (pi dot pj|kl),  (pi dot pj|pk dot pl)

Version 2.8.9 (2017-01-09):
	* New 3c2e integral (pi dot pj|k)

Version 2.8.8 (2016-10-13):
	* Use float128 for high order rys_roots

Version 2.8.6 (2016-07-06):
	* Update incomplete gamma function

Version 2.8.5 (2016-06-22):
	* New integrals <r^2 i|j> and <r^4 i|j>

Version 2.8.4 (2016-05-19):
	* Fix precompile problem for range separation Coulomb integrals

Version 2.8.3 (2016-04-20):
	* New 1e integral p Vnuc cross p

Version 2.8.2 (2016-04-09):
	* Long range part of range-separated Coulomb operator

Version 2.8.1 (2016-04-07):
	* New 3c1e integral <ij|p^2|k>

Version 2.8.0 (2016-03-28):
	* Resolve the optimization bug of LLVM for expression (x+epsilon == x)

Version 2.7.0 (2016-03-03):
	* Adjust for tensor ordering,  from  XX, YX, ZX, XY ...  to  XX, XY, XZ, YX ...
	* Update all tests due to the change of cutoff value estimation

Version 2.6.10 (2016-03-02):
	* Hessian integrals
	* Fix value estimation bug for high order derivatives

Version 2.6.9 (2016-01-22):
	* NMR GIAO 3-cetner 2e integrals

Version 2.6.8 (2016-01-07):
	* Integrals for Breit interaction

Version 2.6.7 (2015-12-26):
	* Integrals (sp i, s, j | k, s, sp l) for Gaunt term
	* Integrals (sp i, s, j | sp k, s, l) for Gaunt term

Version 2.6.6 (2015-12-21):
	* Integrals (i, s, sp j | sp k, s, l) for Gaunt term

Version 2.6.5 (2015-10-28):
	* 3c1e integral generator
	* New 3c1e integrals <ij|r^2|k> <ij|r^4|k> <ij|r^6|k>

Version 2.6.4 (2015-10-19):
	* cart2sph transformation for l=12

Version 2.6.3 (2015-10-15):
	* mixed spinor-cartesian 3c2e integrals

Version 2.6.2 (2015-10-09):
	* 3-center 1-electron integrals
	* mixed spheric-cartesian 3c2e integrals
	* Restore cart2sph transformation interface

Version 2.6.1 (2015-10-07):
	* Expose cart2sph transformation functions

Version 2.6.0 (2015-09-25):
	* API Updates!  To support user-specified gaussian nuclear model,
	the intrinsic nuclear model functions are removed.  Accordingly,
	the 4th element of "atm" argument are changed.

Version 2.5.5 (2015-05-14):
	* Provide sqrtl, expl, fabsl functions when compiler does not
	fully support c99.

Version 2.5.4 (2015-03-02):
	* Change origin of <z>, <zz>, <r> ... integrals.  The existed
	  <z> <r> ... integrals are renamed.

Version 2.5.3 (2015-02-26):
	* Add integral ( p i | nuc | p j )

Version 2.5.2 (2015-02-10):
	* Expose cartesian to spherical transformation

Version 2.5.1 (2015-01-26):
	* Add density fitting integral (sp i sp j | K)

Version 2.5.0 (2015-01-04):
	* Add general 2-center and 3-center 2e integrals
	* Extend code generator for 2-center and 3-center 2e integrals 
	* fix a tensor ordering problem of the code generator

Version 2.4.0 (2014-12-24):
	* Add 2-center and 3-center 2e integrals

Version 2.3.0 (2014-12-14):
	* fix ordering bug in cartesain-GTO integrals
	* optimize cartesian to spherical transformation

Version 2.2.0 (2014-12-01):
	* update cint1e structure
	* add I8 support

Version 2.1.2 (2014-11-25):
	* Change to general compiling flags

Version 2.1.1 (2014-11-16):
	* Disable the compiling of examples by default

Version 2.1.0 (2014-10-16):
	* use cmake

Version 2.0.7 (2014-10-16):
	* Fix bug in examples/c_call_cartesian.c
	* Add new 1e integrals

Version 2.0.6 (2014-10-13):
	* Fix bug in optimizer.c

Version 2.0.5 (2014-09-21):
	* Support angular momentum l=6

Version 2.0.4 (2014-08-16):
	* Add external cart2sph functions

Version 2.0.3 (2014-05-30):
	* Add SOO and SSO integrals
	* Update clisp script to handle new integrals

Version 2.0.2 (2014-05-25):
	* Small optimization

Version 2.0.1 (2014-04-20):
	* Fix bug in optimizer which write data cross array boundary

Version 2.0 (2014-04-20):
	* Change API
	  - Add prefix CINT on built-in function to avoid name conliction
	  - Change function prototype from
		xxx(atm, natm, bas, nbas, env);
	    to
		xxx(atm, natm, bas, nbas, env, opt);
	  - p function are oredered as px py pz for spheric GTOs.
	* Add optimizer which can roughly speed up ERI by 10%

Version 1.2 (2013-12-09):
	* Fix bug for the cutoff threshold in 2e integrals
	* Optimize 2e integrals for Segment-contracted basis

Version 1.1.4 (2013-07-28):
	* Small optimization for memory alloc in cint2e

Version 1.1.3 (2013-06-19):
	* Small optimization for matrix transposition

Version 1.1.2 (2013-06-04):
	* Change C-Fortran code examples.
	* Update testsuits.
	* Add new integrals which appear in DHF-DKB calculation.

Version 1.1.1 (2013-05-29):
	* Fix bug in function f_bra_cart2spinor_sf.

Version 1.1 (2013-05-29):
	* Optimize the transformation from Cartesian GTO to
	  spheric-spinor GTO.

Version 1.0 (2013-01-15):
	* First release.
	* 1e-2e contracted cartensian-spheric-spinor GTO integarls.
	* Common lisp script to generate integral code.

