Allow filters to be predefined, or have all set by default

[XVII]

With the changes in #14 , the filter now defaults to America only. So when we need our end users to test, we have to get them to manually check the filters, increasing the number of steps... They're also not sure what they're ticking -- they're end users.

Can the filters be set using a GET or Hash identifier? This will more allow us to provide pre-configured links to our end users and get results more easily.

[blrchen]

Thanks for the feedback, will add it next week.