Tests: more Node.js tests.

test/node/get_header_names/app.js

@@ -0,0 +1,8 @@
+#!/usr/bin/env node
+
+require('unit-http').createServer(function (req, res) {
+    res.setHeader('DATE', ['date1', 'date2']);
+    res.setHeader('X-Header', 'blah');
+    res.setHeader('X-Names', res.getHeaderNames());
+    res.end();
+}).listen(7080);