Downhill rails

There wasn't time to seek a consensus as to conventions for coding classes.  My style is bound to be different from yours in some hopefully not-too-significant ways.  I debated with myself, for example, whether all the S.E. handlers should go in a single Listener class or whether different siege machines should have their own files.  For modularity I decided to try the latter, hence, it's 'RamMoveListener' instead of just 'WeaponMoveHandler' or some other alternative.