Remove legacy serialization and QPropertyTree (#684)

Remove:
- CryCommon/CryExtension/*
- CryCommon/Serialization/*
- Sandbox/Plugins/EditorCommon/QPropertyTree/*
- All related CryCommon interfaces
- All CrySystem implementations
- Various related Editor classes

Gems/AudioEngineWwise/Code/Source/Editor/AudioSystemEditor_wwise.h

@@ -35,12 +35,6 @@ namespace AudioControls
 
         bool HasProperties() override { return true; }
 
-        void Serialize(Serialization::IArchive& ar) override
-        {
-            ar(m_mult, "mult", "Multiply");
-            ar(m_shift, "shift", "Shift");
-        }
-
         float m_mult;
         float m_shift;
     };
@@ -61,11 +55,6 @@ namespace AudioControls
 
         bool HasProperties() override { return true; }
 
-        void Serialize(Serialization::IArchive& ar) override
-        {
-            ar(m_value, "value", "Value");
-        }
-
         float m_value;
     };