with msvc, the CMAKE_BUILD_TYPE is not taken into account from CMake.
MSVC is multi-configuration and we can change the config from inside msvc.
This new cmake code allows to use this multi-configuration system and
generate automatically the right post-build instruction

Gurobi Solver refactoring

See merge request !27

Merge from ReForm

See merge request !26

Change CoMISoDefines.hh to only export symbols if COMISODLL is defined (same behavior as Windows) to allow building CoMISo as static library without exposing its symbols

Fix compile error with GMM++-5.2, cf. #3

See merge request !25

Implement intermediate_callback() in the IPOPT problem classes to improve responsiveness for progress updates and abort checks.

change gurobi solver interface to accept const refs to vectors

See merge request !24