removing duplicate vectors

[Darrell McCauley]

A small program to remove duplicate vectors in a binary
vector file is available via anonymous ftp at
	pasture.ecn.purdue.edu:/pub/mccauley/grass/v.rmdup.tar.Z

It should be considered pre-alpha, but it works on my test files.
So far, it only removes vectors that are exact duplicates
(all points are the same within threshold, within IEEE "wobbling 
precision" tolerance. see iszero(3)), but in the future
I hope to add a threshold option which will increase this
the tolerance to remove "similar" vectors.

Use at your own risk (read the man page on g.copy first).

--Darrell McCauley