CHANGES: links to release pages added

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@69741 15284696-431f-4ddb-bdfa-cd5b030d7da7

CHANGES

@@ -1,4 +1,10 @@
-CHANGES IN GRASS GIS 7 compared to GRASS GIS 6
+CHANGES current GRASS GIS 7.x compared to previous GRASS GIS 7.x
+
+See list of releases with changelog at
+https://trac.osgeo.org/grass/wiki/Release
+
+
+CHANGES in GRASS GIS 7.0 compared to GRASS GIS 6.x
 
 The graphical user interface based on wxPython (introduced in GRASS GIS 
 6.4) has been enriched with many new features in order to make complex 
@@ -14,8 +20,8 @@ spatial index. Finally, there are a series of new modules to analyse
 raster and vector data; some of the already existing modules were 
 improved and made faster (some even 1000 x faster). 
 
-In total, more than 10,000 changes have been implemented so far with 
-respect to GRASS GIS 6.4.
+In total, more than 10,000 changes have been implemented in GRASS GIS 7.0.0
+with respect to GRASS GIS 6.4.x
 
 For details, please refer to this Web page:
 http://trac.osgeo.org/grass/wiki/Grass7/NewFeatures