+ git-rebase-all command

Signed-off-by: Alexey Shumkin <Alex.Crezoff@gmail.com>
+ git-merge-back

Signed-off-by: Alexey Shumkin <Alex.Crezoff@gmail.com>
git-jump: support "git diff --check"

Signed-off-by: Alexey Shumkin <Alex.Crezoff@gmail.com>