Support adding remote user to an organization

Support adding existing or new users while on organization page.

And deadband session token updates to 1 per 30 seconds

And install initial data in target language. Also configure help tip
popovers to be in the configured, default system language.

Ensure aquireLock doesn't interfere with renew/release

Requires authentication plugins to implement a new AuthDirectorySearch
interface to define the two functions

Previously, the user information could only be modified on the ticket-view
page. For instance, if creating a new ticket for a user, no new information
could be added or modified on the user until after the ticket was created

Fixes osTicket/osTicket-1.8#281

This includes the initial concept of pluggable authentication along with the
initial concept for a plugin management system.

- Remove Client form
- Provide name and email fields for cases where use is not selected (JS
issues)

Fix odd CSS error

Allows the client to be changed on a ticket. Previously, only the
information about the client associated with the ticket was editable. This
patch permits assigning a completely different user to the ticket.

This moves client information like name and email address out of the general
dynamic forms data for a ticket. It really paves the way for the first-class
user of the future.

*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.

...

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