Properly escape text bodies for canned responses

Reviewed-By: Peter Rotich <peter@osticket.com>

files: Provide unified download script

Reviewed-By: Peter Rotich <peter@osticket.com>

This script adds a single download script, 'file.php', which provides access
to files of all types to all users. It uses a HMAC signature system with an
expires time, which allows signed URLs to be sent to external users.

This also fixes an issue with the Http::cacheable() method, where the
last-modified and Etag headers were not properly compared, which resulted in
permanent cache misses by the client.

Sanitize query strings

Reviewed-By: Jared Hancock <jared@osticket.com>

Use http::build_query instead of inline urlencode

Retire l.php

Reviewed-By: Jared Hancock <jared@osticket.com>

filters: Fix several small, major issues

Reviewed-By: Peter Rotich <peter@osticket.com>

  * Fix incorrect mapping to user email address
  * Fix early rejecting of tickets — even if a filter earlier in the
    matching filter list had "stop on match" set
  * Fix ::stopOnMatch referring to incorrect db field

The new logic abandons the early rejection logic in ticket create. Instead,
the normal validation is completed as usual. Thereafter, the filter is
initialized and applied to the ticket. Upon rejection, a RejectedException
is thrown by the ::apply() method of the TicketFilter. The Ticket::create()
method will handle the exception and reject the ticket.

Stop trampolining links via l.php. It was necessary before in order to avoid
the potential of leaking ticket number & email. The authentication mechanism
in place now redirects on successful login.

This is necessary so we can sanitize/encode inputs.

This patch changes the default formatting for text bodies used in emails,
ticket thread, and canned response quoting so that white-space in text
bodies is properly preserved. Previously, the text was treated as raw HTML
and was not properly escaped, nor was the original whitespace preserved.

date search fix

Reviewed-By: Peter Rotich <peter@osticket.com>

staff: Ensure an active admin always exists

Reviewed-By: Peter Rotich <peter@osticket.com>

Record closed-by if opening a ticket with state closed

Reviewed-By: Peter Rotich <peter@osticket.com>

i18n: Fix display of language selection for new templates

Reviewed-By: Peter Rotich <peter@osticket.com>

ui: Implement "enable canned responses" config option

Reviewed-By: Peter Rotich <peter@osticket.com>

orgs: Add support for organization variables

Reviewed-By: Peter Rotich <peter@osticket.com>

i18n: Oops hide erroneous "published" status for internal FAQs

Reviewed-By: Peter Rotich <peter@osticket.com>

forms: Properly display staff/user field requirement

Reviewed-By: Peter Rotich <peter@osticket.com>

html2text: Avoid long, wrapped URLs in a tags

Reviewed-By: Peter Rotich <peter@osticket.com>

faq: Ensure consistent formatting for all

Reviewed-By: Peter Rotich <peter@osticket.com>

lock: Set ticket lock on ticket-view

Reviewed-By: Peter Rotich <peter@osticket.com>

Ensure case-insensitive file extension comparison

Reviewed-By: Peter Rotich <peter@osticket.com>

Do NOT reopen closed ticket on auto-reply

Reviewed-By: Jared Hancock <jared@osticket.com>

forms: Display current value if set to bool FALSE

Reviewed-By: Peter Rotich <peter@osticket.com>

createTicket respects alert/autorespond negatives

Reviewed-By: Peter Rotich <peter@osticket.com>

This affects new ticket by staff as well as honoring the influence of ticket
filters on new ticket, where the status may be set to something other than
the system default. Even the system default may be influenced if it were set
to a closed state derivative.

So the concept is simple: the new status should be set using the standard
logic so that the closed_by staff member, date, events, and other
information is set as normally is when a ticket is closed.

This resolves #1570

This patch removes the selection of canned responses as well as the canned
responses navigation page from the ui when the canned responses feature is
disabled.

Allow usage of something like `%{ticket.user.organization.var}`

Faq articles should be viewed in the .thread-body div in the client portal
like they are in the staff portal.

Since the automatic lock was being acquired but not passed to the autoLock
system, the automatically acquired lock was not being release on away
navigation.

This patch addresses the issue by passing the automatically acquired lock id
to the autoLock system on ticket-view page load and change the ::Init()
method so that the lock id is not cleared with the ::Init() method is called
by the page load.

Ensure that when generating the list of acceptable file extensions, that the list is lower cased, because the extension from the filename will be lower-cased before attempting to find the extension in the list of acceptable extensions.