On branch jan-2021-wip missing NULLC::IsDerivedFromBase

[mingodad]

Trying to build the branch jan-2021-wip I'm getting an error because NULLC::IsDerivedFromBase is not declared/defined, have you forgot to commit something ?

[WheretIB]

I've updated the branch with a definition and support for that function.
I do plan to push additional commits and update master soon.