Task/finishaccountbind

[thommey]

• Central setaccount() function to update account and call binds
• Normalized m->account values (empty string = unknown, "*" = not logged in, otherwise accountname)
• raw and rawt accept wildcards
• moved most of account functionality to irc.mod because it's only relevant in the context of channels
• improved .status reporting for account tracking
• request account-notify and extended-join by default

[thommey]

ready for review again I think

[thommey]

docs need to be generated after merge