Select between the loaded PBLs.
Show the difference of the forecast sprint of completion compared to the
reference PBL.
Merge branch 'master' of
https://github.com/FrankBeeh/ProductBacklogTimeline.git

Conflicts:
	ProductBacklog/PBL1.csv
	ProductBacklog/src/main/de/frankbeeh/productbacklogtimeline/data/ProductTimeline.java
	ProductBacklog/src/main/de/frankbeeh/productbacklogtimeline/view/MainController.java
	ProductBacklog/src/main/de/frankbeeh/productbacklogtimeline/view/main.fxml
	ProductBacklog/src/test/de/frankbeeh/productbacklogtimeline/data/ProductTimelineTest.java