Improve sounds indexer CLI commands

This reworks the CLI commands used to access sounds information from
"sounds show[ soundid]" to "core show sounds" and
"core show sound <soundid>". This also reworks the "sounds reload" CLI
command to fall under normal module reloading ("module reload sounds").

Also, make trunk build when DEBUG_MALLOC is not enabled.

Review: https://reviewboard.asterisk.org/r/2745/
(closes issue ASTERISK-22141)


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@396829 f38db490-d61c-443f-a65b-d21fe96a405b