* obtain bot nick from connection details instead of registry where appropriate
* irc.random_nick works again
* record own hostmask when connecting
* fix web-paste truncation by subtracting length of own hostmask from message length
* set irc.max_msg_len back to 510
* updated IRC numeric 378 to whoishost
* add sprunge.us to WebPaste
PBot now finally supports IRCv3 message tags. The `account-tag`
capability is now enabled for improved NickServ account tracking.
Refactored CAP negotiation. Minor clean-ups in AntiFlood.pm (which ought to
be completely rewritten from the ground-up).
Misc clean-ups and refactoring of various things.