NXCALS-1931 fixed TimeWindow logic
#Merge request template @acc-logging-team - please have a look for approval.
bugs
- now we take all corner cases (hopefully) in consideration when calculating the TimeWindow
minor
- lots of helpful methods and builders with TimeWindow
- full tests on TimeWindow (there was nothing!)
- test-to-code ratio is 4!
Closes NXCALS-1931