mappers: Make the default mapper honor the EXACT_REGION tag in instance creations
mappers: Make the default mapper honor the EXACT_REGION tag in instance creations

StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion