add index.js to coverage to cover dependend file rules/utils/rulesCon…

…figuration.js

gulpfile.js

@@ -15,7 +15,7 @@ gulp.task('quality', function() {
 });
 
 gulp.task('test', function(cb) {
-    gulp.src(['rules/**/*.js'])
+    gulp.src(['index.js', 'rules/**/*.js'])
         .pipe(istanbul()) // Covering files
         .pipe(istanbul.hookRequire()) // Force `require` to return covered files
         .on('finish', function() {