Restrict a regular user's viewing rights to their own events

[aleksisalonen]

As a temporary measure, change the display of events for Regular users. Only display events created by the Regular user in question, and not those created by other users in the same organization.

This should apply to the image modal as well.

This solution is temporary and has drawbacks. It should be replaced by a more robust API+UI-solution in the future (2020 and 2021).