Viewport Detector

As you know with the new version of Bootstrap 3 each viewport is represented by a class name respectively are col-lg- , col-md- , col-sm- and col-xs-.
I created this little extension to help me switch between different viewports while resizing the browser and decide which content should show in which device.
I will add more options to it in the future till then I hope you will find it useful while working with Bootstrap.