Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix typo in a comment.

/* -> /*- for license, minor formatting changes

Get rid of the deprecated *LEN constants in favour of the new
*SIZ constants that include the trailing \0 byte.

Use a single style of multiple inclusion protection for Netgraph headers.

Reviewed by: archie, harti, emax

Declare a variable sized array within a structure using [] rather than [0]
to silence warnings.

Fix GCC warnings caused by initializing a zero length array. In the process,
simply things a bit by getting rid of 'struct ng_parse_struct_info' which
was useless because it only contained one field.

MFC after: 2 weeks

Fix cut and paste error in a comment.
Submitted by: Peter Wemm <peter@freebsd.org>

Since neither archie nor I work at Whistle any more, change our email
addresses to be the more usefu @freebsd.org ones
so we can keep getting bug-reports.
- man pages to follow..

Take advantage of the new unsigned and hex integer types.

Change definition of NG_BPF_HOOKPROG_SIZE() so as not to require
a structure pointer, just the number of BPF instructions.

New netgraph node type, ng_bpf(8). This node type allows you to
apply bpf(4) filters to data travelling through a netgraph network.