Added Tittles and made improvements for following functions:
- ggVisualizeRki
- ggVisualizeIcu
- ggVisualizeEvents.
Also added optional y-axis scale in order to have plots, which have the same size. But I commented them out because if the number of cases exceeds the limit there might occur unwanted bugs. To do that we might discuss on y-axis limit or we can search for other common scaling options.