Add hovers to calendar UI

[raphael-batte]

• rotation start
• parent shift start
• parent shift end
• delete rotation (maybe also as additional description on confirmation Popup)

[Matvey-Kuk]

@raphael-batte please be more specific, examples of texts will be helpful :)

[raphael-batte]

Added tooltips icons to latest UI update

[maskin25]

still don't understand you @raphael-batte :)

[raphael-batte]

We covered this by schedules v2. I think we can close the issue.