Code cleanup. Consolidated test setups into base test class.
Fixed BookChecker + test.
Merge branch 'develop'

Conflicts:
	rosa-archive/rosa-archive-core/src/test/java/rosa/archive/core/AssistedInjectTest.java
	rosa-archive/rosa-archive-core/src/test/java/rosa/archive/core/check/BookCheckerTest.java
Rename ByteStreamGroupImpl -> FSByteStreamGroup. Remove unused factory classes.