- switch to MIT license
- improve compatibility with abstract gringo
- switch build system from scons to cmake
- improve windows compatibility
- make tests and examples python 3 compatible
- bison and re2c are no longer required to build source releases
- update to clasp 3.3.0
- the CLINGOPATH environment variable can be set
to control from where to include files in logic programs - propagators can add variables while solving now
- refactor interfaces (breaking backward compatibility)
- there is just one solve function now
- in the C API do not pass structs by value to callbacks
because FFIs of some languages do not support this
- fix cleanup function
- numerous other bugfixes not listed here