<Someone> noticed that is_damageable used the address of is_rottable
instead of calling it. Unfortunately, there doesn't seem to be a good
compiler warning to detect uses of function addresses as booleans.
to make that field unconditional, otherwise
NetHack won't compile without TEXTCOLOR defined.
Also provides at least an interim solution for the has_color()
problem that Warwick pointed out.
Lastly, Archeologists know touchstones.
