Regardless of the configuration of the help desk registration, allow users
to receive ticket links via email. This patch enables the display and
operation of the ticket access link unless a user login is requested by the
user or specifically required by the system.

Client accounts now that the user is verified either via staff or the
client's email mailbox, there's a much lower risk to showing a verified user
other tickets and virtually no reason that an administrator should have to
turn the feature on.

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