Setup basic rake task for grabbing training data
Use multitask to download all spam files at once
Add URLs to training data
Add missing commas at the end of the hash
Setup task for downloading the files
Add task to normalize downloaded sets

Right now this only handles the spam assassin sets using the known
directory structure pattern that the spam assassin sets follow
Rename spam assassin messages to their MD5 sum

This way we don't have duplicates.
Normalize the CSMINING 2010 spam sets