Merge branch 'ew/repack-with-bitmaps-by-default'

The connectivity bitmaps are created by default in bare repositories now; also the pathname hash-cache is created by default to avoid making crappy deltas when repacking. * ew/repack-with-bitmaps-by-default: pack-objects: default to writing bitmap hash-cache t5310: correctly remove bitmaps for jgit test repack: enable bitmaps by default on bare repos