Allow the use of the PhantomJS remote debugger

This commit adds the '--debugger <port>' option, which triggers
the PhantomJS remote debugger.  The initial output of the terminal
when running the debugger gives more information on how to use
it.

tests/run_from_console.casper.js

@@ -15,7 +15,19 @@ var casper_opts = {
   }
 };
 
-var provide_emitter = function(file_paths) {
+var provide_emitter = function(file_paths, debug_port) {
+  if (debug_port) {
+      casper_opts.child['remote-debugger-port'] = debug_port;
+      var debug_url = ('https://localhost:' + debug_port +
+                       '/webkit/inspector/inspector.html?page=');
+      console.info('[remote-debugger] Navigate to ' + debug_url + '1 and ' +
+                   'run `__run();` in the console to continue loading.' +
+                   '\n[remote-debugger] Navigate to ' + debug_url + '2 to ' +
+                   'view the actual page source.\n' +
+                   '[remote-debugger] Use the `debugger;` statement to ' +
+                   'trigger an initial breakpoint.');
+  }
+
   var spooky = new Spooky(casper_opts, function(err) {
     if (err) {
       if (err.stack) console.warn(err.stack);

tests/run_from_console.js

@@ -20,6 +20,7 @@ program
   .option('--output-html', 'Instead of running the tests, just output the generated HTML source to STDOUT (should be used with .js tests)')
   .option('-d, --debug', 'Show debug output (the "console" event) from the provider')
   .option('-r, --relative', 'Use relative paths in the generated HTML file')
+  .option('--debugger <port>', 'Enable the remote debugger for CasperJS')
   .parse(process.argv);
 
 if (program.tests.length === 0) {
@@ -202,7 +203,7 @@ if (!program.outputHtml && !program.generateHtml) {
     .write("\n");
   //console.log("Running tests %s using provider %s", program.tests.join(', '), prov.name);
 
-  var provider = prov.provide_emitter(file_paths);
+  var provider = prov.provide_emitter(file_paths, program.debugger);
   provider.on('test_ready', function(test_json) {
     console.log('');