even more hg header line endings checks

scripts/check_series.sh

@@ -42,7 +42,7 @@ do
       echo bad hg header in $i
       continue
     fi
-    if ! head -3 $i | grep '# Date ' >/dev/null
+    if ! head -3 $i | grep '# Date .*[0-9]$' >/dev/null
     then
       ERRORS=`expr $ERRORS + 1`
       echo bad hg header in $i