Add a generalized OBO namespace

[jayrbolton]

Adds a namespace for generalized OBO-based ontologies

Related issue https://github.com/kbase/relation_engine_spec/issues/85

• Expands out the types for "synonyms" and "def" under the term
• Consolidates the "isa" and "relationship" edges
• Cleans up the edge IDs
• Generally expands and cleans up some of the field types

[MrCreosote]

Also it looks like consider and replaced by edges are in meta -> basicPropertyValues

[jayrbolton]

Closed in favor of #92 and #93 and #94 and #95