Update 7.5 data

maps.json

@@ -19,6 +19,7 @@
     "grossberg": "Dynasty's Pearl",
     "himmelsdorf": "Himmelsdorf",
     "holmeisk": "Wasteland",
+    "iceworld": "Everfrost",
     "idle": "Yukon",
     "italy": "Vineyards",
     "karelia": "Rockfield",
@@ -51,4 +52,4 @@
     "skit": "Naval Frontier",
     "test": "World of Ducks",
     "tutorial": "Proving Grounds"
-}
+}