Don't use $HTTP_RAW_POST_DATA deprecated in PHP 5.6
Add 'performance_stats' option, so perf. stats can be logged with disabled devel_mode
Allow data-* attributes (#1489860)
Remove unused 'foldertray' container
1489868 - additional_message_headers: correct example X-Originating-IP format
Merge pull request #188 from bbraybrook/1489868

1489868 - additional_message_headers: correct example X-Originating-IP format
Fix searching in addressbook broken with multi-folder search implementation (#1489869)
Unify lists' records and headers height no matter it's td, li or span
Fix/remove tests related to data-* attributes handling
Update copyright year in about template
Update Changelog