Merge upstream r634:646: correctly parse mixed quoted / unquoted text.
Do not suddenly fail on some rulesets if -n (syntax check only) is specified
and ipfw(4) module is not loaded.

MFC after:	2 weeks
MFcalloutng:
Dcoument the new functions added to condvar(9), sleep(9), sleepqueue(9)
KPIs. Also document recent changes in timeout(9) and eventtimers(4).