Pass extra arguments of "upgrade" command to "cubicweb-ctl upgrade"

This allows one, e.g., to request a backup.

entrypoint.sh

@@ -18,7 +18,7 @@ EOF
 fi
 upgrade() {
     echo "upgrading instance"
-    cubicweb-ctl upgrade --backup-db=no --force --verbosity=0 $CW_INSTANCE
+    cubicweb-ctl upgrade "$@" $CW_INSTANCE
     cubicweb-ctl gen-static-datadir $CW_INSTANCE
     cubicweb-ctl i18ninstance $CW_INSTANCE
 }
@@ -27,7 +27,8 @@ case "$1" in
         exec uwsgi --ini /etc/uwsgi/uwsgi.ini
         ;;
     upgrade)
-        upgrade
+        shift
+        upgrade "$@"
         ;;
     db-create)
         exec cubicweb-ctl db-create --automatic $CW_INSTANCE
@@ -40,7 +41,8 @@ Usage:
 
 start                   upgrade and start instance
 db-create               initialize database
-upgrade                 upgrade instance
+upgrade [OPTIONS]       upgrade instance (extra options are passed to
+                        cubicweb-ctl upgrade <instance>)
 
 
 Environment variables: