Remove game/preview functions split in library mode, just let normal procedure run instead:
- Remove tons of HWLIBRARY ifdefs
- Override ParamCount and ParamStr to let GetParams work
- Small fixes here and there
07f3bf8d98a3
Hedgewars.png had a resolution more than twice as high as required; also fixed some (mostly obsolete) code that also contained a typo that would cause a warning/note in clang