Add support for graphical output

## 🚀 Feature Request

Plot bar chart (or other graphs) to compare performance output.

## 🔈 Motivation

A graph gives a better understanding when comparing things.

## 📎 Additional context

```
$ gpucompare --csv-data assets/gpu_data.csv --output=graph
# should output a graph (save an image in current location with a plot)
```
