Build issues on g++ on windows

[vitali-parkhomenko]

When compiling on Windows using g++ (tested on g++-5). I got the following errors:

Scanning dependencies of target EponaMath
[  1%] Building CXX object Pegasus/godlike/Arion/Arion/godlike/Epona/Epona/CMakeFiles/EponaMath.dir/sources/Analysis.cpp.obj
g++.exe: error: /MP: No such file or directory
g++.exe: error: /W3: No such file or directory
g++.exe: error: /MP: No such file or directory
g++.exe: error: /W3: No such file or directory
g++.exe: error: /MP: No such file or directory
g++.exe: error: /W3: No such file or directory
g++.exe: error: /MP: No such file or directory
g++.exe: error: /W3: No such file or directory
g++.exe: error: /MP: No such file or directory
g++.exe: error: /W3: No such file or directory
Pegasus\godlike\Arion\Arion\godlike\Epona\Epona\CMakeFiles\EponaMath.dir\build.make:62: recipe for target 'Pegasus/godlike/Arion/Arion/godlike/Epona/Epona/CMakeFiles/EponaMath.dir/sources/Analysis.cpp.obj' failed
CMakeFiles\Makefile2:240: recipe for target 'Pegasus/godlike/Arion/Arion/godlike/Epona/Epona/CMakeFiles/EponaMath.dir/all' failed
Makefile:150: recipe for target 'all' failed
mingw32-make.exe[2]: *** [Pegasus/godlike/Arion/Arion/godlike/Epona/Epona/CMakeFiles/EponaMath.dir/sources/Analysis.cpp.obj] Error 1
mingw32-make.exe[1]: *** [Pegasus/godlike/Arion/Arion/godlike/Epona/Epona/CMakeFiles/EponaMath.dir/all] Error 2
mingw32-make.exe: *** [all] Error 2

It seems that config files (PegasusBuildFlags.cmake, ArionConfig.cmake, EponaConfig.cmake) doesn't support building this project on GNU compiler on Windows.