[GRASSLIST:3412] 5.7 new coor format

[Radim Blazek]

Writing of the new format for vector 'coor' file was enabled 
in the library. The support for reading is in CVS already 2 weeks.
Switch to the new version should be smooth.

Only the people sharing GRASS native data with other users should
pay attention to this!

If it can happen that you will need to read a data created in a recent version 
of GRASS and your version of SW is old, you should update your GRASS installation. 
Otherwise, if you try to read the new format in the old version of GRASS, 
you get a warning saying that GRASS cannot read the file.

There are 3 versions of the library in the CVS:
1.      <= 30.4. 2004 : writes old , reads old
2. 30.4. - 14.5. 2004 : writes old , reads old/new
3.      >= 14.5. 2004 : writes new , reads old/new 

You can only find problems if you try to read in 1. a vector 
created in 3. 

This is hopefully the last change in the vector format.

Radim