m_joinflood Fix remote joins affecting local joinflood state when the channel is locked

Fixes issue #694 reported by @TurkDesk
m_dnsbl Don't send snotice when the {G|K|Z}line already exists

Fixes issue #717 reported by @Robby-
m_services_account Add workaround for wrong host being displayed in numeric when cgiirc users log in using SASL
Use standard example addresses in configs

`2001:db8::/32` is the [standard][1] IPv6 example address range, using
it also makes it clear when the user has just copy-pasted the example
config and didn't actually whitelist 6BONE for some strange reason.

Similarly, there are example addresses for [IPv4][2] and [DNS][3].

[1]: http://tools.ietf.org/html/rfc3849
[2]: http://tools.ietf.org/html/rfc5737
[3]: http://tools.ietf.org/html/rfc2606
Update example configs/helpop
m_httpd Add timeout option; remove old connections