* Ticket preview crash
* Task view crash

issue: Outlook _MailEndCompose

upgrader: Flush Cache On Upgrade

issue: Org. User Account Status

This addresses an issue where the Upgrader will sometimes use an outdated
cached object and throw an error. This adds a the function to clear the
Model Cache every time the Upgrader runs an Upgrade Patch to get fresh
objects.

Give initial Admin user extended access to ALL departments loaded on
install. This will help new osTicket users, without the Access Control knowhow, see all tickets regardless of the
department while learning the system.

Commit 3944b51d added ability to archive help topics and departments but
failed to port changes default data (yaml files) loaded on install.

This commits adds the correct bits to flags field for both help topics and
departments. It also removes retired 'isactive' field for help topics.

This commits adds ability for agents to configure public queues.

* Customize Columns
* Set default sort & quick filter
* Add supplemental filters (criteria)

To support above features this commit also addresses confusing Advanced
Search UI to make it intuitive when dealing with a Saved Queue vs. Saved
Search vs. Adhoc Search

This addresses an issue where the User’s account status is always 'Active'
in the Organization list no matter what their actual status is. This adds the
account status to the user query which adds the correct status to the Users’
account.

This addresses an issue where Outlook adds weird (and seemingly random)
_MailEndCompose tags to the email body which turns unwanted content into
links. This adds the _MailEndCompose tag to Format::sanitize() so it
will be removed from the email body.

This commit adds var_dump test along with a few enhancements on the test
script.

Only ignore visibility constraints on private "searches" when staff is allowed to search the backend.
Access control is strictly imposed on ALL queues including inherited private sub-queues.

This addresses an issue where you can exploit XSS in the help-topic AJAX
request. This adds a check for a refferal URL and if none it will return
a 403 Forbidden Response.

This addresses an issue where the CSRF Token is displayed in the URL
when you preform a search in the Users Tab. This removes the token from the
request which removes it from the URL.

Updated to fix typo "information" on line 36

* Dont't fetch templates while in a loop
* Tidy up the code

Commit c4579277 introduced an extra administrative security feature to
restrict files access to signed in users only, even  if a user has a valid
& signed download URL. The feature, however, did not take into account
public images & files associated with FAQs and pages such as
landing/thank-you pages.

This commit addresses the shortcoming by adding a reference ID (attachment ID)
to the download/access URL, that can be used to deduce the model/object type
that the file request is associated with. The technique will allow us in the
future to enforce ACL at the file level depending on privacy settings and
the security clearance of the user (agent).

Account for the possibility of agents being deleted

This commit adds user's account username as one of the field to scan on quick lookup;