Monkeys!

Added skeleton files for monkey agents.
Moving standard step(...) function to Body.java

Moved some of the standard boilerplate into Body.java to reduce
copypasta. None of the changes should be in effect in this commit.
API CHANGE!

Noticing that the words "Same Agent" used in many sensors may
give the wrong impression about what's being compared, some
of the sensors have been renamed.

Also: initial domworld simulation skeleton included.
DomWorld first pass

It appears to work!