Merge tag 'v0.9.4' into develop

v0.9.4
Some refactoring in Activity view
Bugfix in form when adding multiple involvements at once
Refactoring query params
First implementation of deleting Items
Some form layout improvements
Improved delete functionality
Revamped stakeholders.py
Merge branch 'develop' into feature/refactor
Revamped activities.py
Revamped stakeholders.py
Merge branch 'feature/refactor' into develop
Revamped stakeholders.py
Merge branch 'hotfix/addqgisdocs' into develop
Bugfix in stakeholder review
Merge remote-tracking branch 'origin/develop' into develop
Release v0.9.5
Merge branch 'release/v0.9.5'