Vacation overview

[viklund]

Please describe the feature

As a manager/nbis staff
I want an overview of when others have vacation
so that I know which of my collegeues are here when.

Detailed description

This probably needs to be refined more but these are considerations to have in mind, in order of priority:

1. It's probably good to see things in a "calendar" like view, similar to a gantt chart
2. It should be possilbe to filter what collegues are visible, this could for example be based on which group someone is assigned in redmine.
3. It should be possible to move start and end date for the view.
   • 3 months is a good "maximum" view.
4. Handle partial absence in some way (ignore it is fine for a first iteration). Partial means present in case it's not handled in some other way.

Additional context