Add some basic functionality to retreive a basic formated date with time

[jmslbam]

You don't want to recreate this logic within every project

11 juli 2017 @ 12:00 till 14:00 - 12 juli 2017 @ 09:00 till 13:00

So I suggest adding this as methods to the Event class that checks if date and times are filled or begin and end time are the same so you can drop the "end" part.