Merge branch 'ps/revision-cmdline-stdin-not'

"git rev-list --stdin" learned to take non-revisions (like "--not")
recently from the standard input, but the way such a "--not" was
handled was quite confusing, which has been rethought.  This is
potentially a change that breaks backward compatibility.

* ps/revision-cmdline-stdin-not:
  revision: make pseudo-opt flags read via stdin behave consistently

diff --cc revision.c
Simple merge