UI changes to make it more user friendly

- Separate 'message' and 'response' variables on New Ticket Notice so they can be styles separately
- Add Thread Event state for 'released'
- Add 'refer' and 'release' permissions to the Role table
- Update install-mysql
- Update patch file name
- Update core.sig
- Set flags in correct place for class.depts.php
- Make sure when opening Ticket, User stays selected if submitted with errors
- Make sure Mail Box Protocol saves correctly when configuring emails

This commit updates a bunch of files and changes a lot of phrases. Basically it extracts "Internal error occurred" from existing phrases.
I've re-ordered the phrases so "Internal error occurred" is always at the end after the actual informative error message.

Example comparison before and after this commit:
Before: 1 Phrase: "Internal error: Unable to print to PDF"
After: 2 Phrases: "Unable to print to PDF." + "Internal error occurred"

Include username when checking if a system email already exists. This
is important for emails that use aliases.

This pass also makes a stride at adding correct punctuation and making error
phrases consistent.

This is my attempt at removing similar texts from the translator work load.
It also makes an attempt at dropping some misspelled words and works toward
standardizing some phrases.

Previously, the create method was used to create a new instance of an orm
model (which would later result in an INSERT when persisted); however, some
classes require or utilize varying parameters to their create() method,
which PHP7 considers an error. Methods in subclasses must be defined with a
calling signature compatible with the parent class.

This patch shifts the concept of model creation to the constructor. Now, the
constructor of ORM models is required to be compatible with that of
ModelBase class. Now that most models do not define a constructor, this is
much easier to control, and much more logical.

Also, remove an issue where assignments on a relationship field to an
instance of a super class of the foreign model would raise an error. This
was previously addressed by re-classing the instance in the
ModelInstanceManager::getOrBuild(); however that design would create
multiple instances of the same object in memory, which defeats one of the
primary design concepts of the ORM. This patch addresses the issue by
allowing super-classes of the declared foreign model in relationship
assignments.

* Fix warning for negative unix timestamps in Misc::db2gmtime
* Fix crash because of parser context passed to getXxx functions
* Fix inability to update email address

This is required with the connection to Dept::getEmail()->send(...)

This patch adds an error to the page if unable to configure the archive
folder and POP was selected as the mailbox protocol. Generally, POP servers
do not support anything but the INBOX

Which indicates permissions are not windowed by an object's department

  * Add trashcan icon for newly-added actions
  * Categorize filter actions
  * Use imperative phrases for action descriptions
  * Drop check boxes from simple actions (like reject ticket)
  * Hide empty forms on new ticket pages
  * Do not store config for nondata fields for actions
  * Implement a multi-use feature for actions, which will allow using a
    action more than once (for instance, multiple email sends)
  * Filter actions are sortable
  * Send email has from address configurable
  * %{user} token is valid as a recipient

Key permissions definition array
Move canned and faq permissions to their respective classes.

Allow for permissions to be registered dynamically. This will
allow for the ability for models and plugins to register permissions.

Previously, osTicket introduced the ability to cascade defaults for the
department and priority to the email mail boxes. However, the validation
checks and display fall-backs were never added.

References:
(Crowdin login required)
http://i18n.osticket.com/translate/osticket-official/148/enus-de#4407
http://i18n.osticket.com/translate/osticket-official/148/enus-de#2379

Multilanguage Support via gettext

- added gettext encapsulations to all texts i thought necessary
- added fallback function for the case that the gettext extension isn't loaded
- added browser language detection
- added gettext to the list of optional extensions in setup
- rewritten some of the texts to use sprintf instead of appending strings
- added german translation file
- removed mark_overdue-confirm from cannedresponses.inc.php

extend multi language support and a fex fixes

- Better detection of translation files
- Added functionality to redirect language codes (see redirecting
language codes)
- Ticket Status can be translated
- The Datepicker can be translated
- Extended functionality of 'testlang.php' to show what language code is
used to translate

Forgotten to apply a patch from RC5 to RC6

- Forgotten to change $var to $vars in line 380 of class.mailfetch.php
- Removed unneeded comment

Added php_gettext as primary translation engine

- Added php_gettext support (thanks to Danilo Segan and Steven
Armstrong)
- php_gettext is now the primary translation engine
- Extended language detection functionality

Add error/misconfiguration checks and fix undefined variables

Use the topic associated with the email if any, and the topic defined as the
system default as the last resort. In either case, the form associated with
the help topic will be added to the ticket, but no data will be put into the
form fields.

Add department setting to limit ticket assignment within department to
department members only. This is necessary for departments with strict
policy on who can access tickets.

The setting doesn't limit team assignment or auto-assignment via help topics
and ticket filters.

Some emails providers (e.g gmail/google) won't deliver emails marked
bulk/autoreply to group email address.

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

Drop old mcrypt class

Spelling, grammar and readability in upgrader documents
  - Tweaked spelling, grammar and wording to make the text of the upgrader
    pages more readable.
Fixed spelling regression
  - Higly —> Highly
Spelling and readability fixes for /include/class.* files
  - Fixed some spelling mistakes
A couple more spelling/readability fixes.
  - More fixes