Comment and stylistic tweaks.
Update CREDITS and CHANGES for TPACKET_V3.

The next release will be 1.5.0; there never was a 1.4.1 release.
More stylistic cleanups.

Also, add a plea to the universe to allow the TPACKET_V3 code not to
have to figure out the largest possible packet size, as that requirement
is the source of huge amounts of pain.