init: clean up periodic_scheduler script and upstart jobs that use it

- Remove script stanzas from upstart scripts. They are unnecesary.
- Properly quote variable names where it makes sense.
- EXTRA! EXTRA! New Curly Braces around variables!

BUG=none
TEST=manual

Change-Id: Iaafb639d6c76b01e94c70f5213a8e432bb1b57dc
Reviewed-on: https://chromium-review.googlesource.com/195689
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Gaurav Shah <gauravsh@chromium.org>
Commit-Queue: Gaurav Shah <gauravsh@chromium.org>
3 files changed