rename local tests to end in test.c

ok beck@ guenther@

tests/pidwraptest.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+./fork_rand > fork_rand.txt
+while read -r a b;
+do
+	if [ "$a" = "$b" ]; then
+		echo "FAIL: $a = $b"
+		return 2
+	else
+		echo "PASS: $a != $b"
+	fi
+done < fork_rand.txt