made BagOfWordVariables general to Map.
Beginning of within to cross-doc coref.
Started
added todos
Removed incomplete macro.
Removed redundant import.
Made Node in hcoref extend CrossDocMention and CrossDocEntity as appropriate.
TacCoref in progress.
TAC Coref setup.
Merge branch 'open-cross-doc'

Conflicts:
	src/main/scala/cc/factorie/app/nlp/hcoref/DebugCoref.scala