Update test framework: fix run_tests.py to support all test files, add auto-import-check for test files

node_modules/@protobufjs/codegen/tests/index.js

@@ -0,0 +1,13 @@
+var codegen = require("..");
+
+// new require("benchmark").Suite().add("add", function() {
+
+var add = codegen(["a", "b"], "add")
+  ("// awesome comment")
+  ("return a + b - c + %d", 1)
+  ({ c: 1 });
+
+if (add(1, 2) !== 3)
+  throw Error("failed");
+
+// }).on("cycle", function(event) { process.stdout.write(String(event.target) + "\n"); }).run();