Displaying field values on various pages and dialogs could result in cross
site scripting exploits.

Fixes osTicket/osTicket-1.8#296

*This is a major redesign / rework of the osTicket base*

This patch drops the concept of static ticket metadata and allows for an
admin-configurable arbitrary data that is attachable to tickets

The system is architected such that the base osTicket install now comes with
a "default" form that has fields for subject, name, email, and phone number.
This form is editable to allow for the addition of arbitrary other fields;
however, the basic fields must remain in order to be associated with a
help-topic and attached to a ticket.

This concept can be expanded to allow for arbitrary data associated with
registered clients or ticket thread items.

Forms are comprised of sections. Sections have a title and instructions
properties and a list of fields. Fields have various implementations to
represent different data such as text, long answer, phone number, datetime,
yes/no, and selections, and are configurable to define the look and feel and
interpretation of the respective form field.

Dropdown lists are represented as "Dynamic Lists", which are
admin-configurable lists of items. Dropdowns can be optionally represented
as Bootstrap typeahead fields.

This also adds the start of a simple ORM which will hopefully be expanded in
the future to support multiple database platforms. Currently, only MySQL is
implemented.

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

After merging the custom logo patch, the logo on the offline page
disappeared. This addresses the issue by exempting the logo.php script for
the offline redirect in client.inc.php

Administrators are allowed to upload one or more logos and then select from
the uploaded logos to set one for the client site. Logos can also be deleted
on settings->pages submission

Add overlay & loading spinner to client interface - shown on form submission to help cut down on double submits.

Use non-minimized css - users can minimize on their own

fixing CSS minification on default theme

changing ticket create/status bottons on client landing page, redoing navbar shadow with css, adding kb icons