- added (very basic) SDL template in CApplication and CEngine
- split project into two targets: colobot_old (dependent on DirectX and WinAPI)
and colobot_new (dependent on SDL and OpenGL)
- moved sound.h/cpp to old/ and created new template in Snd namespace
- added platform-independent dialog boxes in app/system.h/cpp
- changed FPOINT to Math::Point and some functions
from math module to the new implementation
- moved old function and FPOINT struct declarations to math3d.cpp
- removed some unused functions in math module
- fixed some #include dependencies
- moved #define STRICT and #define D3D_OVERLOADS to compile options