add week computation

Author: jugla

README.md

@@ -96,7 +96,10 @@ Since release V4.1.0 : as several linky can be managed , for linky_ref above 1,
 Since release V6.1.0 : cumulative_error is inside *atome_diagnostic* sensor instead of *atome_login_stat* sensor
 
 Since release V7.0.0 : implement Total Energies Server API v2.
-  - as a patch : month, week, year are set to zero
+  - as a patch : week, month, year are set to zero
+
+Since release V7.1.0 : add local computation for week.
+  - as a patch : month, year are set to zero
 
 </details>