Ensures control characters and colours are stripped before parsing.

This should be a no-issue on the Freenode network, but on other networks people
often use colours and such, so those people can not interact with the
bot. Given that such control characters are just intended for humans, removing
them before parsing makes sense.
Merge pull request #20 from killdream/patch-command-parsing

Ensures control characters and colours are stripped before parsing.