Add earth shadow + lunar eclipse finder
Summary:
I've added functionality to calculate and draw the earths shadow disk in moon (or theoretically any) distance.
There is a new eclipse tool in the astrocalc which can find lunar eclipses quite fast. I've overhauled and modularized the original ksconjunct code for that.
The eclipsetool comes with an API that can be extended for other eclipse types.
This is WiP as the eclipse details functionality for generating nice printouts is still missing.
Reviewers: mutlaqja
Reviewed By: mutlaqja
Subscribers: kde-edu
Tags: KDE Edu
Differential Revision: https://phabricator.kde.org/D16303