Featured the Sidebar Builder

**Features Indexed:**
* Enable the Sidebar-Builder or Custom Widget Area Builder.
* Add Support to delete Sidebar that were build by this Axis Framework.
* All the changes are occurred on the `Appearance > Widgets` page.

**Screenshots**

* Builder
![image 1](https://cloud.githubusercontent.com/assets/3774827/4022344/c428a616-2b2c-11e4-8004-76c018c9d3ba.png)

* Manager
![image 3](https://cloud.githubusercontent.com/assets/3774827/4022395/05ac750e-2b32-11e4-866e-e39f3fdb4576.png)