Eoin add domains script

Added a script to generate the "domains = ..." regex from the IANA maintained file at http://data.iana.org/TLD/tlds-alpha-by-domain.txt. (I didn't add any tests because it's a small script which has to be manually copy/pasted anyways--it's otherwise never actually used in code.)
Actually, I don't think it does. search_test.py had all lower-case, and both of these pass: assert_finds_whole_url('LOANFINDERFAST.us') assert_finds_whole_url('LOANFINDERFAST.US'). Both also pass with all upper-case, so I guess it's case-insensitive.

Regardless, I probably shouldn't be randomly switching from lower-case to upper-case, so I'll keep it with the lower-case.