Fixed note copying dlls on some systems

On some Windows systems, compiling would not move libpng12.dll and
zlib1.dll
Added Quadruped flag

Added a flag for some races to be quadrupeds - they have 2 feet slots,
but no hand slots.
Limited Rings

Ability to restrict the number of rings a race can wear.  If you only
have 1 slot, that slot is the horn.