Limit gather rate tooltip to 2 decimal places

Gather rates are not rounded, so after some modifiers are applied, they
appear as ugly decimal numbers.
Limiting them into 2 decimal places for readability and it looks nicer.

Differential revision: D3460
Reviewed by: @wraitii
This was SVN commit r24782.

binaries/data/mods/public/gui/common/tooltips.js

@@ -728,7 +728,7 @@ function getGatherTooltip(template)
 			Object.keys(rates).map(
 				type => sprintf(translate("%(resourceIcon)s %(rate)s"), {
 					"resourceIcon": resourceIcon(type),
-					"rate": rates[type]
+					"rate": rates[type].toFixed(2)
 				})
 			).join("  ")
 	});