Merge pull request #253 from rcordovano/hashdb_comments

Added ability to comment hashes stored in hash databases
Added HashDB JNI unit / regression test.
Added the rest of the asserts to current HashDB tests.
Added lookupInHashDatabaseVerbose unit tests.
Unit test remaining HashDb functions (except for reindexing).
Convert binary blob to text when creating a HashInfo structure.
HashDb unit test improvements.
Merge remote-tracking branch 'upstream/develop' into hashdb_comments
Merge remote-tracking branch 'sam/hashdb_comments' into hashdb_comments