Item5332: Attachment handing needs improvements

Several enhancements needed for Attachment handing

• Generated attachments remain after corresponding dot tags removed
• Generated attachments remain when output formats removed from dot tag
• Too many work_area files created and are also left when dot tags removed.
• Inline attachment is fixed as a PNG. Other types should be permitted.

The plugin is being changed to use a hash to store the file names, output types, and dot tag hash. This is saved in the work_areas directory using the Storable function.

Also, the afterSaveHandler will be added to compare an old and new hash in the work_areas and will optionally clean up any removed output formats or attachments after the save.

-- TWiki:Main/GeorgeClark - 06 Feb 2008