Updated following fields so that they do not pack data into
data_content.content, but use data_content.content, data_content.content1,
etc:
- URL field
- File field
- Picture field
Note that above changes to the way data is stored means that the new
implementation is not compatible with previous version.
Updated textarea field. Added relevant help messages. Added richtext editor
support. Removed ability to restrict allowed formats for the textarea field.
Misc bug fixes and display tweaks.