added error handling for when a class is not found in OQ
refactored to accommodate the BIG nif service queries that deprecate includeSubclasses=true, and use subclassQuery and subclassFilter whenever closure is needed
Upped API version & added model grey tab to disease page
mapStringToSource object (maps string like "MGI" to source object)

Note: Source object ID only has resource ID. Does not contain number at end about the data type.
Fixes #228; disease models now have source object rather than string
Gene page, variant tab; type column no longer undefined

The allele objects in gene JSON blobs don't appear to be well-formed.

1. info.allele[i] has both variant.variant_type and type. variant_type is empty while type is a string.

2. info.allele[i] does not have references though widgets.js is calling references in the evidence column.