New Propositional Functions

Added PFs:

TrenchInFrontOfAgent
BlockInFrontOfAgent
EndOfMapInFrontOfAgent
TrenchInFrontOfAgent
AgentInMidAir
Merge branch 'master' of https://github.com/h2r/affordances

Conflicts:
	src/NewMineCraftDomain/src/minecraft/WorldGenerator/WorldGenerator.java