Add an option to use custom URL params

[gulivan]

Some sites use their own trackers (advert_id, ad_id, etc.)

It would be cool if there was an option to add some custom URL params which will be stripped from the resulting URL.

[jparise]

Because this will greatly increase the complexity of this browser extension (settings management, settings UI, and dynamic regular expressions), I don't intend to support this level of customization.