New spamassassin rule sets added

[forhire]

Jeff gave me a pointer to some additional spamassassin rule sets:
http://wiki.apache.org/spamassassin/CustomRulesets

I have added:
-antidrug which is is a set of rules designed to catch those pesky "pill spams"
-bogus-virus-warnings tries to pick out 'collateral spam' caused by viruses
-chickenpox is a set of rules designed to catch spam like "l.ooks f|or th.is kind of garb+age"

Please keep an eye on your spam folder and let me know if you discover any false positives.