Adding Wordpress' Editor

I have added the WordPress Editor to the list of available field types to choose from. This has been tested on 3.5 and 3.5.1 which I saw that you required this now anyway because of the color picker so this should be good to go!

It enables basic settings right now with the name and id changeable.

This could be extended to enabled a simple ```array_merge()``` with the ```$attr``` argument into the settings argument in wp_editor to allow custom settings passed directly in.