This change makes the resource module use the new API when it embeds media
files (audio/video/Flash), and removes the resourcelib library functions
which were previously used for this.

The old API is still used for embedding non-media files such as PDFs and
HTML.

The URL and Lesson module both used copy/paste duplicates of a section of
resource module code which called the removed functions. I have changed
these too. As a bonus this significantly reduces the duplication involved.

Credit for the rawurlencode() fix goes to Eloy.

The recent change completely removed support for general URIs and enforced strict URL validation which was breaking backwards compatibility and was not user friendly at all.

This patch finally adds full URI support with basic validation and fixes some older xhtml strict issues.

Please note we do not try to explain the difference between URL and URI to our users. Also keep in mind that mod/url has XSS risk and does not do any security validation of the data.

iframe is back in HTML 5, we can safely use it in IE for all text documents because object embedding has multiple problems

Bug fixes:
    * fixed broken flash resizing via URL
    * upgraded Flowplayer
    * fixed invalid context in format_text()
    * all media related CSS moved from themes to filter and resources
    * fixed automatic pdf resizing in resources

Changes:
    * reworked filter_mediaplugin system settings - grouped by player type instead of individual extensions, added more information
    * improved regex url matching
    * removed old unused players, Eolas fix and UFO embedding
    * image embedding moved to filter_urltolink
    * new Flowplayer embedding API
    * accessibility and compatibility tweaks in Flowplayer
    * SWF embedding now works only in trusted texts, it is now enabled by default (works everywhere if "Allow EMBED and OBJECT tags" enabled)
    * new default video width and height

New features:
    * automatic Flash video resizing using information from video metadata
    * Flash HD video support (*.f4v)
    * Flash video embedding with HTML5 fallback - compatible with iOS and other mobile devices
    * Vimeo embedding
    * no-cookie YouTube site supported
    * HTML 5 audio and video with multiple source URLs and QuickTime fallback
    * more video and audio extensions in filelib.php
    * MP3 player colours customisable via CSS in themes
    * nomediaplugin class in a tag prevents media embedding

MDL-22950 adding new component column to the files table, unfortunately this change requires changes in all 2.0dev code, please review all custom code that was already upgraded to 2.0; fixing multiple problems and regressions in mod/assignment

AMOS START
 MOV [displayauto,mod_resource],[resourcedisplayauto,core]
 MOV [displaydownload,mod_resource],[resourcedisplaydownload,core]
 MOV [displayembed,mod_resource],[resourcedisplayembed,core]
 MOV [displayframe,mod_resource],[resourcedisplayframe,core]
 MOV [displaynew,mod_resource],[resourcedisplaynew,core]
 MOV [displayopen,mod_resource],[resourcedisplayopen,core]
 MOV [displaypopup,mod_resource],[resourcedisplaypopup,core]

AMOS END

MDL-21403 hardcoded JS legacy code should not use new $PAGE->requires-> api, switching to html_writer instead + improved ufo embedding

MDL-21187 brand new yui2 lib loading now using the official YAHOO oholoaders which properly resolves all dependencies; please note we are still suing the YUI2 CSS preloading

MDL-20065 new implementation of File module, modules sub-types are being migrated to separate modules; remaining issues to be listed as sub-tasks in tracker