Added regexes for parameter sanitisation

Hello, 

 I noticed that the query parameters were not being sanitised and were an attack vector. With this in mind, I added a capturing regex field to the /endpoint/edit/# route, so a user can specify a regex string in addition to their parameter name. 

![edit-page](https://f.cloud.github.com/assets/458683/249937/b19af400-8b3b-11e2-9d97-d534ae8a4ccc.png)

I also modified the /endpoint route so the listing of query parameters and their associated regex would be displayed side by side.

![list-page](https://f.cloud.github.com/assets/458683/249938/b1e408ac-8b3b-11e2-8f80-9895af884ae0.png)

Cheers!