changed naming scheme for environmental functions
added equality function; conversion to and from Terms is now possible
refactored adding of beliefs a bit
added sample offer for trader
Merge branch 'master' of github.com:robert-schmidtke/map

Conflicts:
	exercise-3/trader.asl
Merge branch 'master' of github.com:robert-schmidtke/map

Conflicts:
	exercise-3/trader.asl