improvements to runner

- colorize succeeded/failed
![image](https://cloud.githubusercontent.com/assets/1767466/3002077/dbe2791c-dd39-11e3-9546-b03fcfd94ebe.png)


- shortened description to a spaceless name. this name can be used with the -c option to specify a config.  This should be easier than trying to figure out the right set of parameters to get the config that you want.

- default domain to test.learn.code.org

- got rid of some browsers not on our whitelist

- when using --html option, have unique output name for each browser config so that you can get all the different outputs when running a bunch of configs