Add almost matching CFaceplateDecoration

Former-commit-id: 0a0483489c

include/Kyoto/Graphics/CColor.hpp

@@ -26,6 +26,8 @@ public:
     mA = a;
   }
 
+  CColor(CColor rgb, float a) : mRgba((rgb.GetColor_u32() & 0xffffff00) | CCast::ToUint8(a * 255.f)) {}
+
   void Set(float r, float g, float b, float a);
   void Set(uchar r, uchar g, uchar b, uchar a = 255) {
     mR = r;