Log Message:
chat/ejabberd: Update to 18.04.

- Don't produce a crash dump during intentional exit
- ejabberdctl: fix parameter parsing
- New hook 'component_send_packet' for sending packet from component
- gen_mod: Carefully validate options list
- gen_mod: Support global module processes
- gen_mod: Remove frontend process support
- gen_mod: Don't crash on invalid module's sub-options
- config: move section about direct-tls for c2s just under regular c2s
  config
- fast_tls: Clear cache on configuration reload
- http: Add support for PATCH http method
- mod_client_state: Add 'csi_activity' hook
- mod_http_upload: Accept characters of any script
- mod_http_upload: Add MIME type for M4A files
- mod_mam: Add commands for cleaning up archives for a given user
- mod_muc: Let a MUC room to route presences from its bare JID
- mod_muc: Introduce new mod_muc option: access_register
- mod_muc_room: Add stubs for affiliation-specific backend callbacks
- mod_muc_log: Fix Code format when logging a MUC room kick/ban
- mod_multicast: Improved
- mod_push: New options include_sender and include_body
- mod_push: Don't notify on stream errors
- mod_push_keepalive: Reset timeout on messages only
- mod_roster: Use 'lserver' for configuration lookup
- mod_vcard_ldap: Fix returning value from mod_vcard_ldap's search()
  callback
- mod_pubsub: Fix notification payload generated by pubsub
- mod_pubsub: Improve pubsub#itemreply implementation
- mod_pubsub: PubSub purge_node must use a transaction
- Utils: Use httpc directly instead of using p1_http wrapper
- Rest: Add flexibility on rest url config
- SystemMonitors: Get rid of useless memory/disk usage warnings
- WebSocket: Pass access option from websocket to c2s