Add new feature to save and recall text snippets (aka canned responses) when composing messages
Make canned response insertion and extraction work with both plaintext and HTML editors
New settings section to manage canned responses
Toolbar and list icons for responses + list header icon for prority column (#1489234)
Keep current selection on IE browsers by adding unselectable=on to link elements
Don't normalize line breaks (doesn't work properly on IE)
Add canned response UI elements to classic skin
Fix indentation
Make result of rcmail::get_compose_responses() always an (indexed) array; add plugin hook for updating user prefs: 'preferences_update'
Use the correct label for responses list header
Allow sysadmins to define static responses which are immutable for the user
Merge branch 'dev-canned-responses'

Conflicts (resolved):
	skins/classic/includes/settingstabs.html
	skins/larry/includes/settingstabs.html
Applied the (modified) patch to extend configuration possibilities of LDAP address books as suggested in #1488753:
- Add option to specify arbitrary replacements of config options with attributes from the bound user
- Allow mapping of group object class => member attribute used in these objects
- Describe the 'member_filter' property for groups config