Adding feature - Test Graph generation

- Added the debugger server GET API - /test/graph that calls Brian's code to generate test graph.
- Added the front-end UI elements to generate graphs. 
- Created line and cycle sample graphs for now (numVertices is a paramter)

Here is a screenshot with a 250 node line graph in Graft! (and the corresponding code)
![screenshot from 2014-05-28 02 18 29](https://cloud.githubusercontent.com/assets/514557/3102840/0e472724-e64d-11e3-8cae-d0f548389df7.png)
![screenshot from 2014-05-28 02 18 37](https://cloud.githubusercontent.com/assets/514557/3102865/50f15b12-e64d-11e3-99ba-1917a2d2bf5d.png)