Timezone warning in core

[Joost De Cock]

PHP throws this:

date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function.
``

It's because of this line in `patterns/Core/Pattern/Pattern.php`

$this->replace('DATE', date('l j F Y') != null ? date('l j F Y') : NULL);

This is the ghost of our MMP history where we used to include the date the pattern was generated in the output. Now, we have the date the pattern was generated in the frontend, so there's no need for this.

As we no longer use the date in the output. So this line can simply be removed.