PHOTOX/ABIN: Pre-release of version 1.1

Version 1.0 was created internally couple years back so we are now targetting version 1.1 for official release.

TODO list for version 1.1 (some items are aspirational)

• finish and cleanup documentation
• merge surface hopping refactor to master
  • finish new MOLPRO interface
  • use overlaps from TC intelligently for monitoring
  • simple overlaps from MOLPRO?
  • adaptive time-step (probably not for this release)
• make PIGLET work (or verify that it is working...)
• make normal modes with NHC thermostat and PIMD working
• verify correctness of ab initio MTS integrator ala Marsalek

This pre-release was created to obtain citable DOI via Zenodo.