patch update

[Joerg Sonnenberger <joerg%britannica.bec.de@localhost>]

Hi all,
http://www.netbsd.org/~joerg/patch.tgz contains the current sources of
the DragonFly incarnation of patch. Based on the changes from OpenBSD,
this provides a number of goodies:
- better detection of re-applying patches
- rejects stay as unified diffs for unified patches
- no arbitrary line limits

The code is well tested and the only relevant change in the last two
years was a bugfix for the obscure edge case of applying a context-less
unified or context diff to the beginning of a file. That case always
reported fuzz, when it shouldn't have done so.

There is one important change that might bite people. SUS says that -b
doesn't take an argument. Newer versions of GNU patch are consistent
with this as well. For pkgsrc users this is chance 1.31 of
mk/platform/NetBSD.mk. There's an open PR for this item.

Joerg