Merge in parts of the old fast_ipsec.4 man page to ipsec.4 and
start updating ipsec.4 man page.
Reviewed by: brueffer, sam (slightly earlier versions), bmah
Approved by: re (bmah)
no cryptodev module.) Should probably create a separate cryptodev man
page (or a link to this one) but for now add enough so folks understand
the relationship between the two.
Prodded by: phk