IProvider: metadata loader

[fprochazka]

CompilerExtension provider interface, for connecting, automatic loading and caching of object validation rules (mainly for Kdyby/Doctrine).

[enumag]

Can you elaborate? Rules for Doctrine entities are loaded from annotations and it works without any problems for me.

[fprochazka]

This requires research, to find out what other extensions which dependent on this one might wanna add to it.
For doctrine its entity metadata and types... for validator it's "insert research results here".

Also, I don't wanna create more IProviders, they're hard dependency. I like this better.

[enumag]

Agreed. I'm using that style in my extensions as well.