Document r270026, nvi 2.1.2-c80f493b038

Sponsored by:	The FreeBSD Foundation
Document r270031, fparseln(3) update to 1.7.

Sponsored by:	The FreeBSD Foundation
Document r270043, '-o key=val' pairing for NFS version
specification.

Sponsored by:	The FreeBSD Foundation
Document r270061, if__nf10bmac(4) merged from head/.

Sponsored by:	The FreeBSD Foundation
Document r270130, unmapped I/O in Xen's blkfront driver.

Sponsored by:	The FreeBSD Foundation
Add attribution for r270130

Sponsored by:	The FreeBSD Foundation