MDL-30903 Accessibility: user profile page uses table headers
MDL-33514 - rss: only retrieve RSS feeds for valid users
MDL-33514 - rss: also exclude suspended users feeds

Thanks Petr!
MDL-30008 Filepicker: correctly handles allowed file types
MDL-33770 Web service: create_groups should not require enrolmentkey

Conflicts:

	group/externallib.php
MDL-9073 Glossary: uncategorised entries are printable
MDL-33957 - Installation - Fixing field lengths so they are long enough for data entry, and don't distort page rendering
Automatically generated installer lang files
MDL-33627 - feedback block now show all feedbacks
MDL-33932_21 - added array_unique()
Merge branch 'MOODLE_21_STABLE' into install_21_STABLE
Automatically generated installer lang files
MDL-32249 completion: Make grade criteria more consistent

Also, round course grades and remove hardcoded string.

Note: This patch also removes the ability to update the course grade
from the completion interface
MDL-30883 question flags: aria attributes for accessibility

Also, update code to use html_writer.

Conflicts:

	theme/base/style/question.css
MDL-33780 question import: strip UTF8 BOM

Previously, if there was a byte-order mark at the start of the file, the
import would just break, which was silly. Much better to just strip it
off.
MDL-32062 question engine: fix re-grading attempts from 2.0

The code to upgrade attempts from before Moodle 2.0 to 2.1 created
attempt data that was not exactly the same as a new attempt created in
2.1+. This did not matter very much - revew and the quiz reports all
worked OK - but it broke on re-grade.

These changes detect the problem data in the re-grade code, an apply a
work-around so that the re-grade gives the correct result.
MDL-34044 completion: Fix regression caused by MDL-26626
MDL-33924 quiz: incorrect foreign key definition.

Thanks to Jean-Michel Vedrine for spotting this.≈
Automatically generated installer lang files
MDL-31802: Remove section summaries from navigation_cache