refactored visualizeData(), simplified empty dataset case, cleaned up old code
refactored visualizeData(), simplified empty dataset case, cleaned up old code

dzhang55/riftwatch,dzhang55/League-of-Legends-Graphs,dzhang55/riftwatch,dzhang55/League-of-Legends-Graphs,dzhang55/riftwatch,dzhang55/League-of-Legends-Graphs