clean up remaining non-generic GetValue uses

OpenRA.Game/GameRules/WeaponInfo.cs

@@ -55,7 +55,7 @@ namespace OpenRA.GameRules
 			return y.NodesDict.ContainsKey( "Versus" )
 				? y.NodesDict[ "Versus" ].NodesDict.ToDictionary(
 					a => a.Key,
-					a => (float)FieldLoader.GetValue( "(value)", typeof( float ), a.Value.Value ) )
+					a => FieldLoader.GetValue<float>( "(value)", a.Value.Value ) )
 				: new Dictionary<string, float>();
 		}
 	}

OpenRA.Game/Widgets/ChromeMetrics.cs

@@ -32,7 +32,7 @@ namespace OpenRA.Widgets
 
 		public static T Get<T>(string key)
 		{
-			return (T)FieldLoader.GetValue( key, typeof(T), data[key] );
+			return FieldLoader.GetValue<T>( key, data[key] );
 		}
 	}
 }