Administrators can disable client edits of ticket information. Hopefully,
this will eventually be replaced by role-based ACLs placed on individual
forms and fields.

The concept of extid is being retired to pave-way for customizatable ticket
numbers.

 - This is necessary so we'll have a name on record - even on user deletion.

Pass the user id (uid) to ticket create instead of unpacked data.

Process inline attachments in thread entry and support inline images in
piped emails

Support inline images across the system, with draft support

Migrate to a single attachment table
    That way we don't need a new table for everything we need to attach an
    inline image to (like a signature, for instance)

Add richtext support for internal notes

Implement images on site pages

* Image paste in Redactor
* Make non-local images optional
* Placeholder for non-local images
* Fix local image download hover
* Don't re-attach inline images

Add routine to import emailed & api files