Release 1.0.0 - state after evaluation submissions complete
Create version 2.0.0-SNAPSHOT for development for 2015 evalutation
Responses how carry a SHA1-based unique identifier string.

Note that Response::hashCode now returns a different value as before
(its previous value was never specified or guaranteed)
Restore previous hashCode to support both 2014 + 2015-style writers
WIP
Switch responses to using SHA1 IDs
Basic data structures for argument linking
I/O for ResponseLinkings
LinkingSpecFormats.openOrCreateLinkingStore
Allow diffing subset of asessments; make fancy output optional

Conflicts:

	kbp-events2014-scorer/src/main/java/com/bbn/kbp/events2014/assessmentDiff/KBPAssessmentDiff.java
Make linkingStore take either SystemOutput or AnswerKey as argument to read
Bugfix: DirectoryLinkingStore always acted as it closed
Allow LinkingStore.readOrEmpty on AnswerKeys as well
Makes response set iterable
Create incomplete ResponseLinking from AnswerKey
Gets rid of EntityNormalizer class
Creating EventArgumentLinkings from ResponseLinking + coref
Refactor ResponseLinking-->EventArgumentLinking alignment to its own class
aligns EventArgumentLinkings back to ResponseSets
Making LinkingStores return Optional<>

Unlike AssessmentStores and SystemOutputStores, the readOrEmpty
strategy is not very meaningful here.