Log Message:
Update chat/ejabberd to 15.06.

Message archiving
- Add support for message archiving in Mnesia or relational databases.

Protocol
- Document protocol support and version inside each module and use that
  info in documentation
- Remove deprecated XEP-0090 Entity Time and XEP-0091 Delayed Delivery
- Don't add body element to MUC subject messages
- Do not bounce normal messages sent to unavailable resource

Admin command-line tool
- Fixed several ejabberd commands
- Allow password with ';' passed in ejabberdctl
- Improve ejabberdctl external module install code, allows better
  error checking
- New ping ejabberdctl command to check if the node is up and running
- New commands for Multi-User chat management: get_room_options and
  get_user_rooms

Configuration
- Add config validation at startup
- Fix include of non yaml config files
- New option hide_sensitive_log_data to hide client IP address in log
- New option net_ticktime, to fine tune Erlang cluster networking
- New option max_users_presence in mod_muc, to avoid broadcasting
  presence packet from users after a chat room has reached a given size

Elixir
- Add correct package version for mix

Security
- New options to configure your own custom Diffie-Helman parameters:
  dhfile and s2s_dhfile

PubSub
- Enforce definition of pubsub node max_items
- Fix pubsub/odbc crash on remote user unsubscribe
- Fix use of publish_only affiliation with odbc backend

Multicast
- Pick first local multicast service, otherwise remote

Databases
- Fix anonymous user login, it wasn't stored in anonymous mnesia table
- Fixed some string/binary issues in ejabberd_odbc
- PostgreSQL storage: added missing sm (session manager) table

Packaging
- Microsoft Windows 64 bits installer
- Provide RPM and DEB binary packages for linux 64 bits.

Clean up
- Remove obsolete doc and win32 files