[Gameplay A24] - Make unlock_shared_dropsites independent from unlock_shared_los.

Since one may start a match with all visible and then the tech is
useless and hides what is underneath.

Patch by: @Nescio
Differential revision: D2999
Reviewed by: @borg-
This was SVN commit r24541.

binaries/data/mods/public/simulation/data/technologies/unlock_shared_dropsites.json

@@ -2,9 +2,13 @@
 	"genericName": "Diaspora",
 	"description": "The extension of trade leads to the permanent establishment of storekeepers and their families in foreign countries, allowing them to exploit the wealth of these countries.",
 	"cost": { "food": 200, "wood": 200, "stone": 100, "metal": 100 },
-	"requirements": { "entity": { "class": "Trader", "number": 3 } },
+	"requirements": {
+		"entity": {
+			"class": "Trader",
+			"number": 3
+		}
+	},
 	"requirementsTooltip": "Requires 3 Traders",
-	"supersedes": "unlock_shared_los",
 	"icon": "diaspora.png",
 	"researchTime": 40,
 	"tooltip": "Allows using allied dropsites.",