make (some) RALint errors nonfatal

OpenRA.Game/Game.cs

@@ -81,6 +81,9 @@ namespace OpenRA
 			ModAssemblies = asms.ToArray();
 		}
 
+		public static Action<string> MissingTypeAction = 
+			s => { throw new InvalidOperationException("Cannot locate type: {0}".F(s)); };
+
 		public static T CreateObject<T>(string classname)
 		{
 			foreach (var mod in ModAssemblies)
@@ -91,7 +94,8 @@ namespace OpenRA
 					return (T)obj;
 			}
 
-			throw new InvalidOperationException("Cannot locate type: {0}".F(classname));
+			MissingTypeAction(classname);
+			return default(T);
 		}
 
 		public static Dictionary<string, MapStub> AvailableMaps;

RALint/RALint.cs

@@ -15,6 +15,7 @@ using System.Reflection;
 using OpenRA;
 using OpenRA.GameRules;
 using OpenRA.Traits;
+using OpenRA.FileFormats;
 
 namespace RALint
 {
@@ -32,6 +33,10 @@ namespace RALint
 
 		static int Main(string[] args)
 		{
+			// bind some nonfatal error handling into FieldLoader, so we don't just *explode*.
+			Game.MissingTypeAction = s => EmitError("Missing Type: {0}".F(s));
+			FieldLoader.UnknownFieldAction = (s, f) => EmitError("FieldLoader: Missing field `{0}` on `{1}`".F(s, f.Name));
+
 			Game.InitializeEngineWithMods(args);
 			
 			// all the @something names which actually EXIST.