Add Support for Gencode Coverage Mapping

[b-f-chan]

Need to add support for gencode coverage mapping --> This involves several sub-tasks which may become separate tickets later. @demariadaniel and @edsu7 to decide details later.

High-Level Sub-Tasks:

• Add functionality to map gencode names and regions (coordinates) to read coverage values in the BAM file
• Determine and add list of priority genes to use in the mapping (we are NOT going to use all 63K+ of genes possible)
• Add functionality to translate the mapping into an Analysis Object in SONG (this likely needs to be its own ticket later) (basically logic to submit into SONG)