Add dropdown in order to execute bulk actions in events

[JoeyStk]

Motivation

Multiple posts can be selected to execute bulk actions. How ever this isn't possible for events and pois, which is necessary in order to automatically translate selected events and pois.

Proposed Solution

Add the dropdown from posts to events and pois using the existing bulk action template. This breaks down into three smaller tasks:

• add the bulk action template
• add the dropdown to select multiple events
• add an option to auto translate the selected events

Additional Context

This is part of the project for Johannes' final exam.