regent: Add environment variable REGENT_INCREMENTAL to enable incremental compilation.
regent: Add environment variable REGENT_INCREMENTAL to enable incremental compilation.

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