Reformatted white space in upload.php.
Marked components/videometa.php for deletion. The file doesn't seem to be in use. We'll delete it later when we're sure.
Refactored and documented the current state of MetaVideo.

- Removed out-commented code.
- Removed unused parameters/variables.
- Added comments and documentation.
upload.php now uses MetaVideo to determine type, id and dimensions of the video.

This moves the youtube/vimeo detecting logic to one place.
Refactored and fixed MetaVideo (for invalid youtube urls).

- It doesn't crash on invalid video urls (the old code would expect a variable $v after parse_url was called on a youtube url, but with invalid urls, this would trigger an error, instead of a safely returning component).
- Errors are stored by err() and returned by render(), instead of echoed and die()ed by err(). This prevents unexpected output (and die) in upload.php.
- Refactored the way in which the type and id of a url are determined (moved it into determineTypeAndId()).
Admin control now shows detailed errors if video url is incorrect.
Cleaned up VideometaController.

- Removed references to markdown controller (from which VideometaController was probably copied).
- Moved the code in getVideometa() to actionGetMeta() because it wasn't used outside this controller.
Reformatted js/controls.js (for readability).
Added support for 2 more youtube link formats.

- The 'embed' format: http://www.youtube.com/embed/6MfJEzVEjCw
- The short format: http://youtu.be/1tmtaQ3FXR8
Removed videometa.php because it wasn't used at all (predecessor of MetaVideo).
Merge branch 'fix-crash-on-unexpected-youtube-urls' into dev