Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

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

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

Fix more typos to be a good example.

Found by: codespell

- Correct grammos in comments and end them with full stops.
- Use "if !" instead of empty true branches.
- Don't hardcode script name in usage message, use $0 instead.
- Cleanup some whitespace.

Usage style sweep: spell "usage" with a small 'u'.
Also change one case of blatant __progname abuse (several more remain)
This commit does not touch anything in src/{contrib,crypto,gnu}/.

Change the script a bit to allow the creation of 'brouted' bridges.
To do this you need to have each top-end connected as well.
IP can be routed and other protocols get bridged..
Also useful when bridgeing two networks while merging them as
machines will work with both old and new netmasks. (well mostly).

Correct a brain-o in the stats output.

PR: 24839
Submitted by: AMAKAWA Shuhei <amakawa@sf.t.u-tokyo.ac.jp>

Script showing how to setup Ethernet bridging using ng_bridge(4).