Wildcard url queries

Thanks for the great library.

I hacked up a way to download all the content prefixed by certain path. I.e. 

`http://www.oalj.dol.gov/PUBLIC/ARB/REFERENCES/CASELIST/*`

This is obviously related to #8, but it's not quite the same thing. I wanted to see if you would be interested in seeing a PR for this? 
