Pull up following revision(s) (requested by manu in ticket #52):
	sys/fs/puffs/puffs_msgif.h: revision 1.81
	sys/fs/puffs/puffs_sys.h: revision 1.85
	sys/fs/puffs/puffs_vnops.c: revision 1.183
Add a oflags input field to open requests so that the filesystem can pass
back information about the file. Implement PUFFS_OPEN_IO_DIRECT, which
will force direct IO (bypassing page cache) for the file.
Pulled up additional changes required for ticket #52.
Pull up following revision(s) (requested by maxv in ticket #54):
	sys/compat/osf1/osf1_file.c: revision 1.42
Ensure nbytes > 0. Otherwise bad things may happen.
Compile-tested only.
ok christos@
Ticket 54.