added unit testing, and started implementing unit tests...phew

node_modules/async/internal/doParallelLimit.js

@@ -0,0 +1,23 @@
+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = doParallelLimit;
+
+var _eachOfLimit = require('./eachOfLimit');
+
+var _eachOfLimit2 = _interopRequireDefault(_eachOfLimit);
+
+var _wrapAsync = require('./wrapAsync');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function doParallelLimit(fn) {
+    return function (obj, limit, iteratee, callback) {
+        return fn((0, _eachOfLimit2.default)(limit), obj, (0, _wrapAsync2.default)(iteratee), callback);
+    };
+}
+module.exports = exports['default'];