Migrated to use MyGene.info v3 API (For API changes, see here: http://docs.mygene.info/en/latest/doc/migration_from_v2.html).
Added caching functions (using requests-cache) for all query types except when using "fetch_all". Can turn request caching on with set_caching(), off with stop_caching(). The cache can be cleared with clear_cache().
Made "fetch_all" feature compatible with Elasticsearch v2.x scroll changes.