Registration: add instructions for finding staff

[fndax]

Normally I'd mention /stats p instead of /join #freenode for obvious reasons, but the channel is actually fairly helpful for registration issues so I made an exception.

Fixes #492

[glguy]

Pointing people to #freenode sounds right to me. I've already heard people ask how they'd find a staff member in the first place. Most registration issues won't need a staff member specifically, so I think that's another win for joining the channel instead of recommending stats p. Of course stats p already confuses new users as it the destination of the output can be a surprise.

An additional comment I'd make is that we might want to tell people how to identify who is staff on #freenode. It might not be obvious to check for @ or a freenode/staff/. Being explicit will help them know who they can trust as authoritative.

[fndax]

@glguy Would adding the following sentence to the end address your second paragraph?

If your problem involves sensitive information, be aware that people with ops in #freenode (designated with @ and a freenode/staff/ cloak in /whois) are network staff and can be messaged in private as needed.

(Bit more technical than I was hoping, but I'm having trouble thinking of better wording)

[swantzter]

For a nitpick I'd say "commonly designated by @" because not all clients does that