Prepare release 2.1.1 (#147)

* Update changelog

* Bump version in version_info.hpp

* Bump version in xcfun.cmake

* Bump version in conf.py

Merge pull request #142 from dftlibs/prepare-v2.1.0

Prepare release 2.1.0

Prepare release 2.0.2 (#138)

Update CHANGELOG.md and bump version number where necessary.

Update CHANGELOG.md

Update changelog

No more warnings (#124)

* No more warnings

* Shut up, clang

* Silence Clang also in Release mode

Fix compilation with GCC 5.4.0 (#117)

This was spotted here: https://travis-ci.org/MRChemSoft/mrchem/jobs/653411396#L559

Merge pull request #116 from robertodr/fortran-int-64

Handle 64-bit integers in Fortran properly

Mint v2.0.0a4

Merge pull request #98 from robertodr/re-fortran

Revamp Fortran interface