Disable PHP angle bracket in PHP files, keep in HTML

It is a widely accepted practice to not put the closing PHP bracket in PHP files. See the popular [PSR-2 guide](https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-2-coding-style-guide.md#22-files) for an example.

With `show_unmatched` this results in a permanent useless warning:
![1](https://cloud.githubusercontent.com/assets/113721/5356494/cd10fbd4-7fa5-11e4-8de8-669ffbd8dabe.png)

In HTML template files the bracket is still useful, as there developers open and close PHP brackets all the time.