- changed tabs to spaces and DOS line endings to Unix
(except in CBot and metafile)
- changed language to English
- fixed #include <d3d.h> in d3dengine.h
- rewritten RotateAngle() function and test for it in geometry_test.cpp
- added conv.h - conversion functions
- added comments in math3d.h and d3dmath.h pointing to new functions
- other minor fixes