Tweak caching topics to fix CEL tests

The Stasis changes in r395954 had an unanticipated side effect: messages
published directly to an _all topic does not get forwarded to the
corresponding caching topic.

This patch fixes that by changing how caching topics forward messages,
and how the caching pattern forwards are setup.

For the caching pattern, the all_topic is forwarded to the
all_topic_cached. This forwards messages published directly to the
all_topic to all_topic_cached.

In order to avoid duplicate messages on all_topic_cached, caching topics
were changed to no longer forward uncached messages. Subscribers to an
individual caching topic should only expect to receive cache updates,
and subscription change messages. Since individual caching topics are
new, this shouldn't be a problem.

There are a few minor changes to the pre-cache split behavior.

 * For topics changed to use the caching pattern, the all_topic_cached
   will forward snapshots in addition to cache updates. Since
   subscribers by design ignore unexpected messages, this should be
   fine.

 * Caching topics that don't use the caching pattern no longer forward
   non-cache updates. This makes no difference for the current caching
   topics.

   * mwi_topic_cached, channel_by_name_topic and
     presence_state_topic_cached have no subscribers

   * device_state_topic_cached's only subscriber only processes cache
     udpates

(issue ASTERISK-22243)
Review: https://reviewboard.asterisk.org/r/2738


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@396329 f38db490-d61c-443f-a65b-d21fe96a405b
ARI: Add recording controls

This patch implements the controls from ARI recordings. The controls
are:

 * DELETE /recordings/live/{recordingName} - stop recording and
   discard it
 * POST /recordings/live/{recordingName}/stop - stop recording
 * POST /recordings/live/{recordingName}/pause - pause recording
 * POST /recordings/live/{recordingName}/unpause - resume recording
 * POST /recordings/live/{recordingName}/mute - mute recording (record
   silence to the file)
 * POST /recordings/live/{recordingName}/unmute - unmute recording.

Since this underlying functionality did not already exist, is was
added to app.c by a set of control frames, similar to how playback
control works. The pause/mute control frames are toggles, even though
the ARI controls are idempotent, to be consistent with the playback
control frames.

(closes issue ASTERISK-22181)
Review: https://reviewboard.asterisk.org/r/2697/


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@396331 f38db490-d61c-443f-a65b-d21fe96a405b