Add schema for gene mentions table
Add schema for gene mentions table

HazyResearch/dd-genomics,amwenger/dd-genomics,amwenger/dd-genomics,amwenger/dd-genomics,HazyResearch/dd-genomics,rionda/dd-genomics,HazyResearch/dd-genomics,rionda/dd-genomics,HazyResearch/dd-genomics,HazyResearch/dd-genomics