Settings check and revise

[razvancrainea]

We need to revise all the new settings files (settings.inc.php), and double check whether all settings are listed, their types are correct, and their hints are suggestive. We might also need to provide a description for some settings, if necessary. This ticket consists of a list of all modules that need to be addressed:

• [x] system_config
• [x] boxes_config
• [x] alias_management
• [x] user_management
• [x] acl_management
• [x] dispatcher
• [x] dialog
• [x] homer
• [x] cdrviewer
• [x] uac_registrant
• [x] smpp
• [x] rtpengine
• [x] dialplan
• [x] siptrace
• [x] clusterer
• [x] permissions
• [x] smonitor
• [x] loadbalancer
• [x] domains
• [x] callcenter
• [x] drouting
• [ ] tviewer
• [x] mi
• [x] rtpproxy
• [x] tls_mgm
• [x] monit