1 turn city vision

[Elefant]

On system requirements, I ran freeciv 3.1.2 on a milk v duo s. 512 mb ram, 1ghz c906 risc v cpu. Aside from a slow Gui (no GPU), it seemed to run fine, ram usage at 290mb at the start of the game.

[Elefant]

So maybe system requirements should be simply a list of supported OS's and disk space usage (min 400mb, recommended 1gb).