r.import/v.import manual: explain -o projection override flag

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@70752 15284696-431f-4ddb-bdfa-cd5b030d7da7

scripts/r.import/r.import.html

@@ -9,6 +9,17 @@ the projection of the location, the input is imported directly with
 
 <h2>NOTES</h2>
 
+<em>r.import</em> checks the projection metadata of the dataset to be
+imported against the current location's projection. If not identical a
+related error message is shown.
+<br>
+To override this projection check (i.e. to use current location's projection)
+by assuming that the dataset has the same projection as the current location
+the <b>-o</b> flag can be used. This is also useful when geodata to be
+imported do not contain any projection metadata at all. The user must be
+sure that the projection is identical in order to avoid to introduce data
+errors.
+
 <h3>Resolution</h3>
 
 <em>r.import</em> reports the estimated target resolution for each 

scripts/v.import/v.import.html

@@ -24,6 +24,17 @@ The list of actually supported formats can be printed by <b>-f</b> flag.
 
 <h2>NOTES</h2>
 
+<em>v.import</em> checks the projection metadata of the dataset to be
+imported against the current location's projection. If not identical a
+related error message is shown.
+<br>
+To override this projection check (i.e. to use current location's projection)
+by assuming that the dataset has the same projection as the current location
+the <b>-o</b> flag can be used. This is also useful when geodata to be
+imported do not contain any projection metadata at all. The user must be
+sure that the projection is identical in order to avoid to introduce data
+errors.
+
 <h3>Topology cleaning</h3>
 
 When importing polygons, non-topological polygons are converted to