This fixes an issue where the PK of ThreadEntry will be NULLed in the
following code

```php
$entry = ThreadEntry::create(array(...));
$entry->save();
$entry->email_info = new ThreadEntryEmailInfo(array(
    'mid' => 'xyzAbc',
));
```

In the above code, the $entry->__set('email_info', <ThreadEntryEmailInfo>)
would be invoked. The ThreadEntryEmailInfo object is new, and so will cause
the local part of the relationship (`id` in this case) to
become null further down in the `__set` method.

This issue is fixed in this commit by removing the NULL assignment to the
new object. This was added in 11322766,
however, it is unclear why the null assignment is performed.

This commit attempts to remove some of the confusing and redundant code to
attach files to thread entries and replace it with a single code base. It
also attempts to remove and error where a single attachment might be
attached to a new thread entry multiple times.

Lastly, it removes the insert followed by an update for emails with inline
images. This should improve performance processing emails as only one trip
to the database is now necessary for thread entries with inline images.

Somehow the attachment security checks got duplicated and messed up. Perhaps
it was a bad merge?

This fixes a regression in 4f8f236d, where
the parameters are sent in the SQL statement to the database. Objects which
are converted to a string must be propertly quoted when placed in the query.

Add year to php to Date Picker (js) translation table

Make sure due date time dropdown display matches the option value.

Stop doing double timezone offset

Simplified executor which uses the mysqli_query() function to process
queries. This method is faster on MySQL as it doesn't require the PREPARE
overhead, nor require two trips to the database per query. All parameters
are escaped and placed directly into the SQL statement.

This executor extends the traditional mysqli_fetch_xxx() methods by casting
non-null numeric field values to PHP numeric types.

This is required because using unbuffered MySQL queries means that no other
SQL queries can be run until the export is finished. Since the Staff model
will lazily query the config table, the queries need to be fetched in
advance.

This adds a new concept to the ORM iteration mechanisms and allows iterating
over very large queries without caching the records neither in the result
set nor in the model cache. It also implies using the mysqli_query() method
rather than the prepared statement model, as unbuffered queries with the
prepared statement system are much slower.

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.

This duplicates the custom logo code to allow for custom login backdrops. A
new page is added to the "Company" settings page which allows for management
of the uploaded custom backdrops.

Also, rename other apc_xxx functio to the new apcu_xxx equivalents available
since PHP 5.4.

Use APCu, if available, to cache the compiled model meta data.

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.

This commit attempts to remove all coding standard warnings emitted by PHP
7.0.

Default to system default of staff doesn't have page limit set.

Credit: @antriver PR#2951

Strip tags on text input field to prevent potential XSS exploit.

Let textarea widgets parse and clean input based on configured text format.
Add cleanup routine to ThreadEntryBody
Clean response/note inputs

Conflicts:

	include/class.forms.php
	include/class.ticket.php

Encoded entities can be used to bypass safety checks
Don't remove iframe when using xml_dom to balance tags

This fixes an issue, where the department manager cannot be excluded from
the new ticket alert if the members of the department are checked.
Considering there is a separate selection for the manager, this patch
adjusts the system so the manager of the department only receives the new
ticket alert if the manager checkbox is set. Otherwise, only the members of
the department other than the manager receive the alert.

Automated $uid is initialized as null - this resulted in the initial field
getting a null id.

To avoid date format ambiguity the datepicker replaces entered date with a
standard 'ISO 8601' date format on form submission. The system however fails
to use datepicker's format on post-back, resulting in invalid date on
subsequent submit.

This pull request addresses the issue by making sure reflected date uses the
format datepicker expects.

'strtotime' uses local timezone without taking into consideration the user's
timezone. This pull requests simply makes sure user's entered timeframe
range is converted to db time before it's used in a query.