Updated plugin checking logic

* Fixes #6183
* Also changed a bunch of console.logs to process.stdout.write,
  so the command line output is cleaner

src/meta/build.js

@@ -99,6 +99,8 @@ function beforeBuild(targets, callback) {
 	var plugins = require('../plugins');
 	meta = require('../meta');
 
+	process.stdout.write('  started'.green + '\n'.reset);
+
 	async.series([
 		db.init,
 		meta.themes.setupPaths,
@@ -210,7 +212,7 @@ function build(targets, callback) {
 		}
 
 		winston.info('[build] Asset compilation successful. Completed in ' + totalTime + 'sec.');
-		callback();
+		callback(null, true);
 	});
 }