Split REFLECTION_REFLECT_INTRUSIVE macro into a code-injection macro and a reflect macro.
Split REFLECTION_REFLECT_INTRUSIVE macro into a code-injection macro and a reflect macro.

Hopefully, this allows for easier testing of the reflection-unrelated bits of the big macro, and possible finding an alternative that has fewer problems (e.g. not supporting templates).

erikvalkering/smartref,erikvalkering/smartref,erikvalkering/smartref