add comment in subversion paragraph

README

@@ -19,13 +19,18 @@ Bugs:
 
 Subversion:
 -----------
-The code is maintained under revision source control software subversion under:
-https://svn.mpl.ird.fr/us191/tsg-qc/trunk/
-
-You can get last update local copy with svn update.
-
-If you try to modify code, never change or modify by hand the NetCDF descriptor
-file @netcdf_native/tsgqc_netcdf.csv
-
+ The code is maintained with the revision control software subversion under:
+ https://svn.mpl.ird.fr/us191/tsg-qc/trunk/
+
+ You can get the last update in your local copy with the command:
+ $ svn co https://svn.mpl.ird.fr/us191/tsg-qc/trunk/ .
+ and keep your working copy up-to-date with:
+ $ svn update
+
+ If you try to modify code, never change or modify by hand the NetCDF descriptor
+ file @netcdf_native/tsgqc_netcdf.csv
+ This file is obtained by a transformation of the Excel file tsgqc_netcdf.xls
+ with Matlab class dynaload running on Windows system. 
+ For any changes, contact me by mail at Jacques.Grelet_at_ird.fr