[mvparent] Get rid of useless error messages

Test the presence of files in the directory before to call mv, in order
to avoid useless mv error message.

mvparent/mvparent.sh

@@ -26,5 +26,13 @@ fi
 echo "Move the contents of « $rep/$cible » into « $rep »…" >&2
 
 cd "$rep"
-mv "$cible"/* "$cible"/.[!.]* .
+
+if [ "$(echo "$cible"/*)" != "$cible/*" ] ; then
+	mv "$cible"/* .
+fi
+
+if [ "$(echo "$cible"/.[!.]*)" != "$cible/.[!.]*" ] ; then
+	mv "$cible"/.[!.]* .
+fi
+
 rmdir "$cible"