Merge branch 'ks/rebase-no-git-foo'

Mentions of "git-rebase" and "git-am" (dashed form) still remained
in end-user visible strings emitted by the "git rebase" command;
they have been corrected.

* ks/rebase-no-git-foo:
git-rebase: clean up dashed-usages in messages

diff --cc git-rebase.sh
Simple merge