#125 - Initial Drag and Drop

+ add sortable library
+ add font awesome icon to indicate draggable
+ added styles for draggable
+ made rows sortable, as well as created reorderGame function

Per discussions with @scottmeng, at the moment the request sends game slug and rank (see #169). The rank is zero-based, so if that needs to be changed let me know.  Also if we switched to a serialized JSON string, i will change this accordingly (shouldn't be difficult).

I am using [this library](https://github.com/RubaXa/Sortable) for the drag and drop. Would you rather have the minimized css? I forgot to change it (used regular in case we needed to debug) but both are in the folder.

Gif:
![Gif of drag and drop](https://s3.amazonaws.com/quickcast/5023/16804/quickcast.gif)