[Suggestion] ETA for ground missions

[Zesty]

It'd be nice if we could get a predicted arrival time when launching a craft and (more importantly) a day/night indicator for when arrival will be.

Something like:

Target: Landing Site-X
ETA: 2 hours (put the icon for night missions here if it will be during night)

[Meridian]

1/ ETA was implemented here: https://openxcom.org/forum/index.php/topic,11733.msg160767.html#msg160767

2/ I don't know the math behind globe shade levels (per date, time, location and seasons options)... if someone wants to give it a try, I'm open