Updates debian package with dependency to yui-compressor, which generates min versions of some libs (strophe plugins).
Adds dependency to jquery debian package.
Adds prosody config to conf.avail and enable it in conf.d so we don't wipe prosody config on installing meet.
Moves config.js in /etc/jitsi/meet.
Removed unused files.
Adds dirs file.
Fixes purging configuration.