added separate icon for kill

i've added in the stop icon with ui-variable red color for when the program is halted simply because this is really different than an actual error. we have 4 distinct things happening. loading or running, exit 0 completion, exit code or error, and ctrl-c kill or stop process. because of this i feel we need all separate icons to indicate feedback for each one. i've attached screenshots of them in action.

![screen shot 2014-03-06 at 3 51 00 pm](https://f.cloud.github.com/assets/1441464/2351246/f89f1512-a579-11e3-8bd9-701fbf911af6.png)
![screen shot 2014-03-06 at 3 51 15 pm](https://f.cloud.github.com/assets/1441464/2351250/fc2387e0-a579-11e3-9e84-3d515a6de4e5.png)
![screen shot 2014-03-06 at 3 51 22 pm](https://f.cloud.github.com/assets/1441464/2351258/05b68de8-a57a-11e3-8d9d-aa77e681223e.png)
![screen shot 2014-03-06 at 3 51 46 pm](https://f.cloud.github.com/assets/1441464/2351263/144c5c3e-a57a-11e3-88f1-e432f38303ed.png)