Fix HTML part detection for some specific message structures (#1488992)
Better handling of session errors in ajax requests - do page reload
on 403 Forbidden response (#1488960)
Re-implement rcube_db::num_rows() to ensure backwards compatibility
Fix storing 'safe' flag on a message. The key for session value should include
folder name. A message with the same UID may exist in another folder.
Fix "rcmail is undefined" error in HTML attachment preview - regression
from commit d30460ad2fc0f78ce44d474fa2c466d660596d27, small improvements
Fix javascript error when window name (for window.open()) in IE8 contains a dot

Conflicts:

	program/js/app.js
Fix wrapping of text lines with the same length as specified length limit
Fix so forward as attachment works if additional attachment is added by message_compose hook (#1489000)
Prevent from re-adding the same forward attachment on compose page refresh

Conflicts:

	CHANGELOG
Make mime.types common locations list OS-aware
Workaround for some versions/systems where finfo_open() with second
argument doesn't do the same as with no 2nd argument as it should
Consider alternative table names from config when running DB updates
Fix handling of some conditional comment tags in HTML message (#1489004)

Conflicts:

	CHANGELOG
Added two tests for HTML comments handling in rcube_washtml class
Fix javascript error in IE9 when loading form with placeholders into an iframe (#1489008)
Better fix for IE9 issue with document.activeElement error (#1489008)
Remove composer template because the new plugin system isn't ready yet
Add some extension/mimetype aliases to fix some quirks in attachment type validation (#1488891)
Ensure backwards compatibility by considering old-style skin_path attribute for <roundcube:include ...> tags
Match regex on multi-line sql statements
Fix vcard folding when outputing already generated vcard