Merge branch 'so/log-m-implies-p'

Merge branch 'so/log-m-implies-p'

The "-m" option in "git log -m" that does not specify which format,
if any, of diff is desired did not have any visible effect; it now
implies some form of diff (by default "--patch") is produced.

* so/log-m-implies-p:
  diff-merges: let "-m" imply "-p"
  diff-merges: rename "combined_imply_patch" to "merges_imply_patch"
  stash list: stop passing "-m" to "git log"
  git-svn: stop passing "-m" to "git rev-list"
  diff-merges: move specific diff-index "-m" handling to diff-index
  t4013: test "git diff-index -m"
  t4013: test "git diff-tree -m"
  t4013: test "git log -m --stat"
  t4013: test "git log -m --raw"
  t4013: test that "-m" alone has no effect in "git log"