Add sun arrow

[gtrus21]

Describe the idea

Add a third arrow to the radius ruler - to the sun (at night it can be replaced with an arrow to the moon)

Expected behaviour

Alternatives you've considered

Context

[vshcherb]

1. This should be optional - possibly separate widget ?
2. Also arrow should show "Sun incline" as number
3. In case sun in zenith arrow should show to the North
4. Also color should vary on maximum - Grey (under horizon < 0 ) - Red (0) Yellow (for maximum height)

[gtrus21]

3. if the sun is at its zenith, then you must either point the arrow at the sun in the same way, or remove it, or replace it with some kind of circle.
4. It is better to always use the same color so as not to get confused.