Update blacklist.js

Vastly increases speed with precalculated regular expressions. Much better blacklist/whitelist handling. Cleans userinput for safer string checking. .exec would be even faster for a few cycles as an optimization, as we do not need to use /g

Removed O(N^3) cycles, now it is O(N^2) worst case, average of just O(N).

You can also remove the slow tag on this script.