Event Periods

[seandenigris]

We have at least the following use cases:

1. Pinpoint - the plane landed @ such and such time
2. Window - the current implementation i.e. a defined and variable start and end time and date

Then there's another axis:

1. Date - the American Revolution started on Xyz
2. DateAndTime - the meeting started on 1/1/2020 @ 10am

Maybe in case no 1 immediately above, it's really that the time is just unknown or irrelevant