BReference: missing const cast when building a BReference<const>

* The internal BReference is on a non-const object so it can increment
and decrement the reference count, so we need to cast the const away.

headers/os/support/Referenceable.h

@@ -176,7 +176,7 @@ public:
 
 	BReference(const BReference<const Type>& other)
 		:
-		fReference(other)
+		fReference(const_cast<Type*>(other.Get()))
 	{
 	}