for per-method interface documentation
by mkdoc.pl.
implement timeouts on network reads
and use them in dns client.
also added locks on i/o to ensure writes
are not interlaced.
R=r
DELTA=340 (272 added, 25 deleted, 43 changed)
OCL=25799
CL=25874
get rid of _ on private names in net.
fix os_test file name list.
newline not needed on Errorf.
R=r
DELTA=305 (34 added, 2 deleted, 269 changed)
OCL=25047
CL=25047