Clean up setting saving.

Rather than saving only those settings specified explicitly in
$SettingGroups, check $_REQUEST for all settings listed in
$SettingList.
Actually save response and review preference instructions.

DERP
Screw the pcPaper column.

Tags are clearly better.
ContactInfo gains a `data` field, to be JSON.
Accept <h2>.
Support a clickthrough license for the submissions page.
Message system improvements.

And actually save 0 as a response word limit.
Multiconference: Replace ${confname} in email sender addresses.
Don't read nonexistent column.
Correct reference to unset property.
Review saving improvement: Only report unready review if review unready.
Formula fix: Allow changing old formulas.

bugs bugs bugs bugs bugs
Formulas: Review loops compile to integers.

Specifically 'sum(tag:whatever)' will never display a check mark.
Also, "false" results display as empty, rather than 0.
Formulas: Add support for 'true' and 'false'.
Formula fix: Exploded scores are strings, so '===0' doesn't do what we want.

Need to '==0', and cast the score to an int.
Formulas: Add all() and any() aggregate functions.
Help improvements for formulas.
Formulas: Add 'isprimary', 'issecondary', 'isexternal'.

These return true if ... well the obvious thing. Matt Welsh request.
'Your Name' and 'you@example.com' are not valid primary admin information.
Fix bogus JSON for fallback review form.

Single quotes leave backslashes in there.