* 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

The staff portal has a feature where the date fields are converted to
YYYY-MM-DD prior to form submission. However, this code was not ported to
the client portal. Therefore, for non-US date formats (d/m/Y for instance)
would not be processed properly by the server and would be nulled prior to
validation.

Only one file is supported at a time now; but at least the files are saved
and displayed in the event of validation errors.

On some setups, IE v10 on Windows 7 at least, text added to the Redactor
editor after an image is inserted (via the image popup dialog for instance),
will not be retrieved via the ::get() method and so will not be submitted
with the form submit button.

This patch introduces a workaround by manually calling ::sync() for the
Redactor when the submit button is pressed — just before the form is
submitted.

Also add a drop-down list of common links include ticket links and login
pages for both agents and end users.

And add translations for the draft mechanism

Previously, the display of the button was incorrect and more than one button
might have been displayed.

htmLawed stripped/discarded <div> tags nested inside inline tags such as
<a>. The previous replacement engine would replace <img> tags with <div>
tags and would cause the HTML to be corrupted by htmLawed.

This patch uses <span> tags which have CSS rules to be displayed as
inline-blocks. This should stay truer to the normal sizing and placement of
the original <img> tag.