Merge branch 'rs/tighten-alias-help'

"git -c alias.foo=bar foo -h baz" reported "'foo' is aliased to
'bar'" and then went on to run "git foo -h baz", which was
unexpected.  Tighten the rule so that alias expansion is reported
only when "-h" is the sole option.

* rs/tighten-alias-help:
  git: show alias info only with lone -h