Merged support for non-BoundingRegionShelve-tracks
Reverted incorrect change
Added support for ##FASTA (ignoring the sequences)
Added GffCategoryGenomeElementSource. Made FastaGenomeElementSource a sliceSource for improved performance. Updated tests.
Merge https://github.com/sveinugu/gtrackcore into pytables. Some of the tests lead to error because of bugs in the _add_slice_element_as_rows method.

Conflicts:
	gtrackcore/input/adapters/TrackGenomeElementSource.py
	gtrackcore/input/core/GenomeElementSource.py
	gtrackcore/preprocess/GESourceManager.py
Merge branch 'pytables' of github.com:brynjagr/gtrackcore into pytables