[GRASS5] v.in.mapgen ported

[Hamish]

Hi,

I've just rewritten the v.in.mapgen.sh module from GRASS 5 & added to
6.1-CVS as v.in.mapgen.

Supports line data from both Mapgen and Matlab format ascii files.

Nice mapgen coastline data can be found at NOAA's coastline extractor:
  http://www.ngdc.noaa.gov/mgg/shorelines/shorelines.html


'Matlab format' is just "x y" line vertices with different lines 
separated by a row of "NaN NaN".


Note the menu listing for this goes nowhere in 6.0.0. (fixed)



enjoy,
Hamish