fix(codegen): Fixes various code gen issues. Adds better embedded serialization support (#688)

* Adds save flag support (see `ElvenGlasses` for an example)
* Updates AOSAttributes so they are code genned
* Fixes embedded object support by adding an `IRawSerializable`
* Fixes various inconsistencies in serializing with codegen

Projects/SerializationGenerator/SerializableMigration/SerializableFieldFlagComparer.cs

@@ -0,0 +1,31 @@
+using System.Collections.Generic;
+using Microsoft.CodeAnalysis;
+
+namespace SerializableMigration
+{
+    public class SerializableFieldFlagComparer : IComparer<(IMethodSymbol, int)>
+    {
+        public int Compare((IMethodSymbol, int) x, (IMethodSymbol, int) y)
+        {
+            var (methodSymbolX, orderX) = x;
+            var (methodSymbolY, orderY) = y;
+
+            if (ReferenceEquals(methodSymbolX, methodSymbolY))
+            {
+                return 0;
+            }
+
+            if (ReferenceEquals(null, methodSymbolY))
+            {
+                return 1;
+            }
+
+            if (ReferenceEquals(null, methodSymbolX))
+            {
+                return -1;
+            }
+
+            return orderX.CompareTo(orderY);
+        }
+    }
+}