Updated Template for new dotnet runtime

- Added Submodule 'Xml-Beef'
- Use .slnx as solution-file
- Automatically set correct path to ScriptCore in Project files

GlitchyEngine/src/Extension/System/String.bf

@@ -34,5 +34,16 @@ namespace System
 		{
 			SetF((IFormatProvider)null, format, params args);
 		}
+
+		public int PreviousIndexOf(StringView subStr, int endIdx, bool ignoreCase = false)
+		{
+			for (int ofs = endIdx - subStr.Length; ofs > 0; ofs--)
+			{
+				if (Compare(Ptr+ofs, subStr.Length, subStr.Ptr, subStr.Length, ignoreCase) == 0)
+					return ofs;
+			}
+
+			return -1;
+		}
 	}
 }

GlitchyEngine/src/Scripting/ScriptEngine.bf

@@ -83,6 +83,8 @@ class EngineClasses
 
 static class ScriptEngine
 {
+	public const String ScriptCorePath = "Resources/Scripts/ScriptCore.dll";
+
 	private static Scene s_Context ~ _?.ReleaseRef();
 
 	private static EngineClasses _classes = new .() ~ delete _;
@@ -200,7 +202,7 @@ static class ScriptEngine
 		// this means that we cannot easily reload changes to ScriptCore.
 		// Since this basic infrastructure shouldn't really ever change we could make a tiny
 		// library with only that enabling us to reload script core.
-		CoreClrHelper.Init("resources/scripts/ScriptCore.dll");
+		CoreClrHelper.Init(ScriptCorePath);
 	}	
 
 	/*static void InitMono()