Ingame gathering speed tooltip

[elexis]

Since promotion and techs (fish) change the gatherrate, it should be shown in the selection details and panels.

Notice some stone mines / pyramids have other gatherrates (stone.ruins). From the players point of view, it would be nice to show these if these actually occur on the map, but that might be ugly to implement. Another idea might be to add this information to the tooltips, but that seems wrong as the translations would have to be updated everytime someone changes that balancing. Third option would be to continue to ignore it, but it would be nice to reveal this fact to players. (Maybe a loading tooltip?)

[wraitii]

I had added that in the tooltip when a unit was selected and you hovered a ressource for my GUI mod. I think it's the nicest solution.

[Imarok]

Move tickets to In-game UI as UI & Simulation got some sub components.

[Silier]

In ​24549:
Display gather rates per subtype

Currently gather rates per subtype of resource are averaged , which hides important information for players. Therefore they do not realise some units may be better collecting grain or fruit.

Also removing todo from the code.

Thank @Stan for fruit and grain icons without cursor and new fish.

Differential revision: ​D3310
Accepted by: wraitii
Comments by: Freagarach, Nescio
Ref: #4077