New editor

Inspired by http://www.freebase.com/query and some discussions. 

This new editor includes a checkbox to enable profiling (enabled by default) and a way to retrieve the schema of a relation. 

![screen shot 2014-04-07 at 19 58 29](https://cloud.githubusercontent.com/assets/589034/2639487/b55afa14-bec9-11e3-9ea8-06aeda675b17.PNG)