Merge branch 'ds/revision-show-pulls'

"git log" learned "--show-pulls" that helps pathspec limited
history views; a merge commit that takes the whole change from a
side branch, which is normally omitted from the output, is shown
in addition to the commits that introduce real changes.

* ds/revision-show-pulls:
  revision: --show-pulls adds helpful merges

diff --cc revision.c
Simple merge

diff --cc revision.h
Simple merge