Fixing GFFparser => GFFParser, adjusting to naming scheme.
Adjustments to naming scheme.
Removing unused code.
Changing Feature to be immutable, adding FeatureBuilder.

Includes tests.
Using @Immutable annotation somewhat more.
Changing some comments.
Marking RNA2GeneIDMapper as final.
Fixing GFFstruct=>GFFStruct to naming scheme.
Updates to .gitignore.
Refactoring GFF parsing somewhat.
Fixing RefSeq downloading.
Adding final annotations, annotation of non-public interface.
Adding author information.
Removing unused UCSCDownloader.javar.
Some code simplification.
Added API comment.
Renaming function.
Removing unused code.
Beginning Builder for TranscriptInfo.
Merging TranscriptDataParser and UCSCKGParser.