glance: stop using deprecated notifier_strategy

Change-Id: Ic796f0ad57db45bf053312ad10815461528030b3
Remove unneeded guest conf values

Reasons:
 - guest service doesn't depend on "sql_connection" value any more;
 - "exchange_control" already set in trove-guestagent.conf.sample to "trove";

Change-Id: Ifbdb21ac4639d86cf7775634f5b31cfb9739b49f
Closes-Bug: #1256046
introduce if/then & for/do rules

we mostly have a consistent style on if/then & for/do in devstack,
except when we don't. This attempts to build a set of rules to
enforce this.

Because there are times when lines are legitimately long, and there
is a continuation, this starts off ignoring if and for loops with
continuations. But for short versions, we should enforce this.

Changes to make devstack pass are included. The fact that the
cleanup patch was so small is pretty solid reason that this is
actually the style we've all agreed to.

Part of a git stash from hong kong that I finally cleaned up.

Change-Id: I6376d7afd59cc5ebba9ed69e5ee784a3d5934a10
Merge "glance: stop using deprecated notifier_strategy"
Merge "Remove unneeded guest conf values"
Merge "introduce if/then & for/do rules"
Merge branch 'master' of https://github.com/openstack-dev/devstack