Added new functions to editor api - set/get_text so the
original form text can be determined from an editor.

When calling use_editor() you should first call set_text() with
the text that will be inserted in the form element.

There is also a new scheduled task for cleaning Atto autosave drafts.

This changes the setting htmleditor in the user table from a 0 or 1 column
to a user preference for the name of their preferred html editor.

- use finfo to determine mimetype of a file only when it is unknown from file extension
- display filetype icon and mimetype in filemanager based on file extension
- fixed a small issue with specifying extension instead of group in file_get_typegroup()
- allow only web-compartible image types when embedding into editor or using in database field
- created new groups web_video and web_audio to use in resource module

Revert "MDL-30843 and MDL-30842 - accessibility compliance: Add <label> for form input text and select tag"

This reverts commit f9f281b8.

The permissions are now going to be verified as part of the weekly release process.

CV S: ----------------------------------------------------------------------

Text of help pages Read carefully, Write carefully and Ask questions
moved to wiki by Helen. Text formatting help removed, to be
re-introduced properly in editors rewrite. Unused editorhelp form
element removed completely.

MDL-21695 renaming ->help_icon() to old_help_icon() and going to introduce new help_icon() with new parameters and detailed debugging - hopefully this will help during the conversion to new help

MDL-21217, MDL-21198 simplified/improved outputlib help icon related apis + several fixed regresions

MDL-20700 coding style cleanup - cvs keywords removed, closign php tag removed, trailing whitespace cleanup

Reverting various checkins related to this bug.
PLUS... proper 1 line fix included (merged from STABLE19)

Missed the format field for textarea.

Merged from STABLE_19

MDL-16493 file and picture element migrated; waiting for file picker to mature, presets not finished yet

data mod whitespace cleanup - there are already many accessibility related changes and fixes that are not backportable anyway and merging from previous versions is not expected

* image galery preset accessiblity fixes MDL-7822
* xhtml fixes
* fields now use s() and p() where needed
* added labels to all fields - imporved accessiblity for adding of new entries
* some other general bugfixing and cleanup

it is still not finished though, expect some more commits tomorrow