Merging from MOODLE_16_STABLE:
Fix for MDL-8515: Prefixing chat messages with a slash should not hide the
user's name unless it's a special command we handle.

I completely removed the emoticon handling case, but it seems like it was
not needed for a long time now? Emoticons work just fine without it.

MDL-8629 - Outputting correct messages during redirection after forum posting with mail-now selected

Added format_string() around $course->shortname in calendar.view.php

Someone must have fixed this earlier, because there are no more tables. However I found the use of the align attribute which I replaced with inline CSS style=\"text-align:right\"

Added support for array of tested browsers to be passed to ajaxenabled()
Merged in from MOODLE_18_STABLE

Safari 2.0 and Opera 9.0 are now detected and supported for YUI. However, preliminary tests show that drag&drop behaviour is very slow on Opera and user-unfriendly on both browsers. A YUI debug window also pops up on Safari.

I added a unit test for ajaxlib.php

Issue MDL-8417
Merged from MOODLE_18_STABLE

When restoring numerical questions, don't create duplicate unit definitions. Merged from MOODLE_18_STABLE.

Also do some validation on the units entered to stop duplicate units being defined.

 Merged from MOODLE_18_STABLE.