chanop.py has issues with banmask

[Mikaela]

1. chanop.py doesn't follow irc.network.ban_mask_default My irc.network.ban_mask_default is set to *!*@*$host
2. chanop.py has different syntax for banmask that doens't include help text Mine is set to *host and I would expect it to work like the first example, ban *!*@*host.

Adding the * there helps with webchat users at freenode as *!*@IP only matches webchat and normal clients, but doesn't match kiviirc while *!*@*IP matches all three.

[SamStrongTalks]

If no one else is working on this, I can take a shot at it.