add calculator to Xfce ISO

[sebo505]

I noticed that we ship no calculator with Xfce Iso. The way I test distributions/ISO's is to boot into the live environment, play around a bit and start some apps. I always start at least the calculator. Well, there is none on our Xfce ISO. So I installed mate-calc. It fits well to Xfce and does not pull in dependecies like gnome-calculator does. As long as we have it in repo, I suggest to add mate-calc to Xfce ISO (or add alternative calculator package to repo).

[davidjharder]

mate-calc does look the simplest. Our options from the current repo:

• speedcrunch: active-ish, but no recent releases. Doesn't look like a calculator by default
• kcalc: drags in many frameworks deps
• gnome-calculator: at first glance, not an enormous number of deps
• mate-calc: not bad

[sebo505]

gnome-calculator only pulls in libgee and libgtksourceview5

[malfisya]

gnome-calculator is a libadwaita app so it will be out of place on XFCE (without extensive theming). I thought we could add galculator as new package but it is been dead for years. So my vote is on mate-calc.