Fixed bug with highlighting things in closures.

Naturally the first file I open after my previous PR was merged is one containing closures, something I'd forgotten PHP added (even though they've been there since 5.3).

The issue was that the regions defined for `[ ]` and `( )` pairs (`phpParent`) didn't contain the new cluster I created for the folded control structures (`@phpClControl`).  

Since PHP 5.4 it's been possible to define arrays using the `[ ]` syntax, which means closures (and therefor control structures) can now be present inside `[ ]`s.  To account for this, I add the `@phpClFunction` and `@phpClControl` clusters to that region's `contains=` list and removed `@phpClInside` since that's contained in `@phpClFunction`.

Thanks for your help and patience with these pull requests, this has been a great learning experience for me and something I've wanted to learn for a while.