Really fix test runner this time

Still doesn't work as we don't return failure from the Python fails
if doctests fail.  But the test runner script is correct now.

run-tests.sh

@@ -1,9 +1,15 @@
 #!/bin/sh
 PYTHONPATH="Lib:$PYTHONPATH"
 export PYTHONPATH
+TESTS=`git grep -l doctest Lib/`
 ret=0
-git grep -l doctest Lib/ | while read test; do
+for test in $TESTS; do
 	echo "Running tests in $test"
-	python $test || let ret=ret+1
+	if ! python $test; then
+		let ret=ret+1
+	fi
 done
+if test $ret != 0; then
+	echo "$ret source file(s) had tests failing" >&2
+fi
 exit $ret