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

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

This is the stock 2.3 file. Since someone majorly SPAMMED the
repository by NOT vendor importing the virgin 2.0 sources, CVS
had no idea what to do here.

Back out the botched attempt to update to gnu grep 2.3 (lots of history
was lost). Restore original version to try and avoid breaking the build
while David O'brien does a proper set of imports and merges.

Requested by: obrien