Replace _.createCallback reference in readme with _.callback. [ci…

… skip]

README.md

@@ -35,7 +35,7 @@ A list of upcoming features is available on our [roadmap](https://github.com/lod
  * [_.constant](http://lodash.com/docs#constant) & [_.property](http://lodash.com/docs#property) function generators for composing functions
  * [_.contains](http://lodash.com/docs#contains) accepts a `fromIndex`
  * [_.create](http://lodash.com/docs#create) for easier object inheritance
- * [_.createCallback](http://lodash.com/docs#createCallback) for extending callbacks in methods & mixins
+ * [_.callback](http://lodash.com/docs#createCallback) for extending callbacks in methods & mixins
  * [_.curry](http://lodash.com/docs#curry) for creating [curried](http://hughfdjackson.com/javascript/2013/07/06/why-curry-helps/) functions
  * [_.debounce](http://lodash.com/docs#debounce) & [_.throttle](http://lodash.com/docs#throttle) accept additional `options` for more control
  * [_.findIndex](http://lodash.com/docs#findIndex) & [_.findKey](http://lodash.com/docs#findKey) for finding indexes & keys