This allows administrators to select a default value for selection fields
deriving from Custom Lists. This has been implemented on the ChoiceField,
but was forgotten on the SelectionField

This addresses cases where incoming emails doesn't include charset and
mailbox may include non-ascii characters.

  * Use the title of "Information" with internal tag of "info"
  * Add "Visibility" column to UI and retire "Required" and "Internal"
    columns
  * Add visibility selection to new fields and show visibility to the user
    information fields when displayed on the ticket details form
  * Make the visibility settings translatable
  * Use constants internally for visibility configuration detection
  * Use a larger input when managing the information HTML content
  * Fix validation errors for new fields
    * Enforce new field name uniqueness
    * Enforce new field name character validation

Under certain intermittent circumstances (usually a significant number of
ORM queries), the ORM will trigger a MySQL error:

Commands out of sync; you can't run this command now

Usually this MySQL error is related to buffered versus unbuffered queries.
However, the ORM already uses buffered queries (MySQL calls it
"store_result"). In this case, it appears there is some sort of race between
fetching the result metadata before configuring the statement for buffering.
(By "race" I mean that the error is not reliably triggered).

This patch seems to fix the issue by configuring buffering before fetching
result metadata — necessary to configure the fetching (output) phase of the
statement.

This is similar to the section break but doesn't have the <hr> element
before it and allows for HTML input (including images)

Improve info display & formatting
Only show 8 chars of the last commit

Add ticket status properties field before loading init data.

Hide multi selection option for typeahead selections

Consider current status settings to determine if a ticket is reopen-able
Show a warning on staff's ticket view if the ticket is not reopen-able

This will allow administrator to indicate if end users are allowed to reopen
tickets in a particular closed status.

Hiding a field triggers visibility check on dependent fields
Use jQuery specific value getters

This will be useful for maintaining arbitrary list of items. ListObject
should be used in the place of ArrayObject

Fix issue that fails for get names on incorrect formats. Ex: J.Everybody

This is necessary to avoid confusion vs. closed state.

Also fix crash if the [name] of a widget element started with a digit
character.

This allows administrators to define a regular expression to filter content
entered into short answer fields by agents and endusers. With the new
visibility feature, the regular expression input is only shown if the
regular expression validator is selected.

This allows fields to specify a visibility constraint that will be evaluated
in real time in the browser to automatically show and hide fields that
should be hidden based on values of other fields in the same form.

Validation is not performed on fields server-side if they are considered
invisible when submitted.

In some cases, a POST might be sent to the server and there be no draft. In
such a case, neither the draft nor the body of the page can be inspected for
images. Even worse, in some cases the previous images might be unlinked from
the article without being relinked. Therefore, the images will no longer be
linked to the page and will likely be purged from the system.

Previously, the code would scan the email headers until it found a positive
match from any of the email headers scanned. Additionally, it would attempt
to find the user from the tagged email references header. However, this
algorithm assumed that the references header was constant and predictable in
its ordering. Recent tests with Gmail prove otherwise in some tests.

This patch changes the system so that only the tagged reference header is
included in the References header, and it will scan all items in a header
(namely the References header) until both the thread and a user are
identified. If a user can be identified, the thread and user are returned.
Otherwise, the first thread hit is returned.

Redirect to tickets listing page when a ticket is resolved or closed via
status change.