Update EventModel.md
Update EventModel.md

In einem EventTemplateContainer kann immer nur genau ein EventTypePlugin dargestellt werden.
Wird mittels UniqueConstraint [EventTemplateContainer.eventTemplate, EventTemplateContainer.containerName] sicher gestellt.
minors
Merge remote-tracking branch 'forte/feature/plugin' into feature/plugin
Merge remote-tracking branch 'ecamp/devel' into devel
Merge branch 'devel' of https://github.com/ecamp/ecamp3 into feature/day/job

Conflicts:
	module/EcampWeb/view/layout/layout.twig