XFilter

- Added the ability to add custom Regex filters using /xf addFilter <filter> <number of replacement characters>

- If a filtered word is used within another word it will block it. This is both good and bad, for example if I were to block 'word' then 'wording' would be '****ing' and 'expowordilicious' would return 'expo****ilicious'. In the first case it is good, you're blocking a usage of the word but in the second you're blocking its random occurrence in another word.