Link to #7733 also.
Fix scope of SSLError.
Add kSPKIHash_GoogleG2 to the pins of flashproxy-reg-email and facilitator-email-poller.

I for sure now see this pin using facilitator-email-poller, running from
the main facilitator. May as well make it uniform everywhere.
IMAP4.error includes IMAP4.abort, and we want to catch both.
close and logout only if we logged in.

I was getting a NameError referring to "imap" if the exception happened
in imap_login.
Use safe_format_addr in flashproxy-reg-http.
Alphabetize options and make options structs match.
Rearrange a constant.
Say just "default" in place of "by default".
Various man page markup fixes.
Add some missing options to man pages.
Regen man pages.
Align option table columns.
Add new flashproxy-reg-email pin to ChangeLog.

This is potentially visible to users.
Tolerate other URL parameters in client regisration lines.
Send client-transport=websocket in registrations.
Add --transport option to reg programs.
Add --transport to flashproxy-client.

Also pass it to registration helpers.
Add --transport to man pages.
Factor -4, -6, and --unsafe-logging into "common" options.