Changed the searching for class templates to work in depth.

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

src/AST/ASTContext.cs

@@ -112,7 +112,8 @@ namespace CppSharp.AST
                     break;
                 case "ClassTemplate":
                     foreach (var module in TranslationUnits)
-                        yield return module.FindClassTemplate(name) as T;
+                        foreach (var template in module.FindClassTemplate(name))
+                            yield return template as T;
                     break;
                 case "Function":
                     foreach (var module in TranslationUnits)

src/AST/Namespace.cs

@@ -341,10 +341,13 @@ namespace CppSharp.AST
                 .FirstOrDefault(t => t.USR == usr);
         }
 
-        public ClassTemplate FindClassTemplate(string name)
+        public IEnumerable<ClassTemplate> FindClassTemplate(string name)
         {
-            return Templates.OfType<ClassTemplate>()
-                .FirstOrDefault(t => t.Name == name);
+            foreach (var template in Templates.OfType<ClassTemplate>().Where(t => t.Name == name))
+                yield return template;
+            foreach (var @namespace in Namespaces)
+                foreach (var template in @namespace.FindClassTemplate(name))
+                    yield return template;
         }
 
         public ClassTemplate FindClassTemplateByUSR(string usr)