add support for extra es6 features

FEATURES.md

@@ -99,6 +99,23 @@ console.log(`${x} + ${y} = ${x + y}`); // "5 + 10 = 15"
 ```javascript
 ```
 
+## Constants
+
+```javascript
+```
+
+## Computed property names
+
+```javascript
+var obj = {
+  ["x" + foo]: "heh",
+  ["y" + bar]: "noo",
+  foo: "foo",
+  bar: "bar"
+};
+
+```
+
 ## Property name shorthand
 
 ```javascript

README.md

@@ -41,9 +41,11 @@
 | [Rest parameters](FEATURES.md#rest-parameters)                       | ✓           |
 | [Template literals](FEATURES.md#template-literals)                   | ✓           |
 | [Modules](FEATURES.md#modules)                                       | ✓           |
-| [Array comprehension](FEATURES.md#array-comprehension)               |             |
-| [Property name shorthand](FEATURES.md#property-name-shorthand)       |             |
+| [Property name shorthand](FEATURES.md#property-name-shorthand)       | ✓           |
+| [Computed property names](FEATURES.md#computed-property-names)       | ✓           |
+| [Constants](FEATURES.md#constants)                                   |             |
 | [Destructuring assignment](FEATURES.md#destructuring-assignment)     |             |
+| [Array comprehension](FEATURES.md#array-comprehension)               |             |
 | [Generators](FEATURES.md#generators)                                 |             |
 
 ## Installation

lib/6to5/transform.js

@@ -95,7 +95,9 @@ transform.test = function (actual, expect, opts) {
 };
 
 transform.transformers = {
+  computedPropertyNames:    require("./transformers/computed-property-names"),
   propertyNameShorthand:    require("./transformers/property-name-shorthand"),
+  constants:                require("./transformers/constants"),
   arrayComprehension:       require("./transformers/array-comprehension"),
   arrowFunctions:           require("./transformers/arrow-functions"),
   classes:                  require("./transformers/classes"),