fix #308 search sub-namespace

Author: chaowlert

src/Mapster.Core/Register/AdaptAttributeBuilder.cs

@@ -31,7 +31,7 @@ public AdaptAttributeBuilder ForAllTypesInNamespace(Assembly assembly, string @n
         {
             foreach (var type in assembly.GetTypes())
             {
-                if (type.Namespace == @namespace && !this.TypeSettings.ContainsKey(type))
+                if ((type.Namespace == @namespace || type.Namespace?.StartsWith(@namespace + '.') == true) && !this.TypeSettings.ContainsKey(type))
                     this.TypeSettings.Add(type, new Dictionary<string, PropertySetting>());
             }
 

src/Mapster.Core/Register/GenerateMapperAttributeBuilder.cs

@@ -23,7 +23,7 @@ public GenerateMapperAttributeBuilder ForTypes(params Type[] types)
 
         public GenerateMapperAttributeBuilder ForAllTypesInNamespace(Assembly assembly, string @namespace)
         {
-            this.Types.UnionWith(assembly.GetTypes().Where(it => it.Namespace == @namespace));
+            this.Types.UnionWith(assembly.GetTypes().Where(it => it.Namespace == @namespace || it.Namespace?.StartsWith(@namespace + '.') == true));
             return this;
         }