Fix handling of identities_level=4
Remove redundant ini checks
Add rcube_db::escapeSimple() method for backward compat.

Conflicts:

	plugins/virtuser_query/virtuser_query.php
Fix links to PHP PDO drivers manual
Fix typo simpleEscape -> escapeSimple
Add rcube_db::escape() method, fix escapeSimple() to use escape instead of quote()
Allow onload attribute on iframe element
Small code optimization

Remove function argument as a local variable is used.
Fix handling of deprecated boolean value of reply_mode option (#1489052)
Fix DB error when creating a new contact and a group is selected (#1489051)
Fix a typo
Fix list of required configuration options (#1489055). Removed support_url, and db_table_*
Fix unintentional messages list jumps on click in Internet Explorer (#1489056)
Fix incorrect handling of leading spaces in text wrapping
Fix another text wrapping issue