repository: add a groups option

Plumb in support for passing --groups to `repo init`.

BUG=brillo:134, chromium:299943
TEST=`./cbuildbot/run_tests` passes

Change-Id: I5bff9847bf6ad89c6f77abffaf4d248ab9306a14
Reviewed-on: https://chromium-review.googlesource.com/246900
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
1 file changed