MBF21

MBF21 is the next step in the classical / conservative feature progression from doom to boom to mbf. The project has these goals: Fix bugs and miscellaneous issues in mbf. Maintain backwards compatibility with the features of mbf. Make it easy to modify previously hard-coded elements of the engine. Add "low hanging fruit" features for maps and dehacked that are in demand. Make changes that are easy to adapt into existing source ports and tools. Maintain the classical / conservative flavour of boom / mbf.