Account for TZ offsets for event durations and next occurrence#499

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armiiller wants to merge 2 commits intoice-cube-ruby:masterfrom PagerTree:master

+17-1

Commits on Oct 7, 2021

Adds correcting logic for events with durations so we account for the offset of events spanning zones (utc offsets)
armiiller
committed

Commits on Oct 11, 2021

Remove the added shift_time_by_validation, this was due to bad testing
armiiller
committed