Merge branch 'pb/request-pull-verify-remote-ref' into maint

"git request-pull" learned to warn when the ref we ask them to pull
from in the local repository and in the published repository are
different.

* pb/request-pull-verify-remote-ref:
  request-pull: warn if the remote object is not the same as the local one
  request-pull: quote regex metacharacters in local ref