Merge branch 'en/backfill-fixes-and-edges'

The 'git backfill' command now rejects revision-limiting options that are incompatible with its operation, uses standard documentation for revision ranges, and includes blobs from boundary commits by default to improve performance of subsequent operations. * en/backfill-fixes-and-edges: backfill: default to grabbing edge blobs too backfill: document acceptance of revision-range in more standard manner backfill: reject rev-list arguments that do not make sense