Wpa enterprise support

Hi,
I tested It on my Nexus 4 (4.4) and several other devices (4.1) with PEAP/TTLS and other options.

Works great.

Sorry if something wrong it was my first experience (java/mvn/github) and I glad to fix it.
I don't want to drop support for Android 4.0.x (API 15) yet. This won't work since this key isn't defined in earlier SDKs. I think more reflection is needed to make this work.