If the Return-Path header does not match the From header, emails are significantly more likely to be blocked by spam filters.

This patch forces the return header to match the from address without having to change php.ini and therefore works properly on servers that have multiple apps sending from multiple email addresses for example shared hosting, multiple support emails in one instance etc.

Add callback filter to standard iteration method to skip deleted items.

Use file id instead of attachment id to unset new
Get new files objects as array

Credit @Jared

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

Use org_id to filter users to update on organization delete

If something like members__staff is considered leaving the Team model,
and the `members` relationship is nullable, and the `staff` relationship is
not, in the context of the compiled SQL statement, the second join should
also be considered nullable (LEFT join), because otherwise inconsistent
results would be returned from the query.

In other words, if a count is considered as an annotation to the Team model
instances, Teams with zero members should still be considered as valid teams
and should be selected with such an annotation. Before this patch, however,
the join between TeamMember and Staff would have been an inner join instead
of a LEFT join, which could skew the database results.

This fixes an issue where the CDATA table is updated with the OLD version of
an answer after it is updated. That is, after an answer is updated, the
CDATA table is also updated to reflect the change; however, the old content
of the answer value is used when updating the CDATA value.

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.

Make config items caching class instance based.

This partially reverts a change in the ORM changing the QuerySet::all()
method to return an Iterator rather than an array. I spent a while proposing
a patch to replace usage of all() with iterations; however, I cannot propose
a valid reason to abandon the previous methodology.

This reintroduces the previous behavior: calling all() will yield an array
of results from the QuerySet's iteration system.

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.