[GRASS-dev] v.surf.rst fixes

[Helena Mitasova]

Markus,

after some testing here,
it seems that the latest fixes in  v.surf.rst submitted in dev_6  
branch (grass65)  work
and if there are no objections they can be included in the GRASS64  
release.
The changes:

- fixed segfault if only scol is given and other instances of wrong
   combination of parameters (including having quietly interpolating
   categories for 3d vector data if you forget to set layer=0, which I  
did many times)
- fixed running out of memory problem for large point data sets (usually
   caused problems for 10mil + points)
- added -z flag (but layer=0 still works, in case you have some  
scripts with that)
   to interpolate the z-coordinate values

There is still an outstanding problem with offset2 int variable  
overflow (on my machine
for rasters around 40,000x40,000), I am just waiting the hear from  
Glynn on what the
correct fix is - I am hoping it is as simple as changing the type of  
offset2.
If anybody knows how to handle these issues properly I can post more  
details,

thanks,

Helena