Docs update, added CORS to some responses.

lib/cors-anywhere.js

@@ -7,19 +7,20 @@ var regexp_tld = require('./regexp-top-level-domain');
 
 var help_file = __dirname + '/help.txt';
 var help_text;
-function showUsage(res) {
+function showUsage(headers, response) {
+  headers['content-type'] = 'text/plain';
   if (help_text != null) {
-    res.writeHead(200, {'content-type': 'text/plain'});
-    res.end(help_text);
+    response.writeHead(200, headers);
+    response.end(help_text);
   } else {
     require('fs').readFile(help_file, 'utf8', function(err, data) {
       if (err) {
         console.error(err);
-        res.writeHead(500, {});
-        res.end();
+        response.writeHead(500, headers);
+        response.end();
       } else {
         help_text = data;
-        showUsage(res); // Recursive call, but since data is a string, the recursion will end
+        showUsage(headers, response); // Recursive call, but since data is a string, the recursion will end
       }
     });
   }
@@ -92,7 +93,7 @@ var getHandler = exports.getHandler = function(options) {
       //                                          2:host
       if (!match || (match[2].indexOf('.') === -1 && match[2].indexOf(':') === -1) || match[4] > 65535) {
         // Incorrect usage. Show how to do it correctly.
-        showUsage(res);
+        showUsage(cors_headers, res);
         return;
       } else if (match[2] === 'iscorsneeded') {
         // Is CORS needed? This path is provided so that API consumers can test whether it's necessary
@@ -112,7 +113,7 @@ var getHandler = exports.getHandler = function(options) {
         res.end();
         return;
       } else if (corsAnywhere.requireHeader != null && req.headers[corsAnywhere.requireHeader.toLowerCase()] == null) {
-        res.writeHead(400, {'Content-Type': 'text/plain'});
+        res.writeHead(400, cors_headers);
         res.end('Missing ' + corsAnywhere.requireHeader + ' header!');
         return;
       } else {

lib/help.txt

@@ -1,3 +1,5 @@
+This API enables cross-origin requests to anywhere.
+
 Usage:
 
 /               Shows help
@@ -6,3 +8,5 @@ Usage:
 
 The protocol can be omitted. It defaults to http:, unless port 443 is specified.
 
+Demo        :   http://rob.lekensteyn.nl/cors-anywhere.html
+Source code :   https://github.com/Rob--W/cors-anywhere/