Feature/issue 165

Adds functionality that allows the user to whitelist certain potential trackers which need to be whitelisted to work. E.G. Youtube comments. This feature is already present in the chrome version but this would add it to the firefox version. CC @jsha for review. 
AFAIK there  is no way to load another file from an addon from within a content script. If you know of a way to do this then I could load the file with an XHR request and do some templating to insert the variables that I need.