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.)
you should `from __future__ import print_function` at the top of the file and use print(...)

With that, this becomes
print(
    'long line long line long line '
    'moar stuff moar stuff moar stuff'
)