[isabelle-dev] NEWS: generated code as proper theory export

[Lars Hupel]

> In 2012 we eliminated all Makefiles from AFP: I did not know that some
> came back, or chose to ignore it.

~/work/afp (default)$ find thys/ -name Makefile
thys/Buchi_Complementation/code/Makefile
thys/Formal_SSA/Makefile
thys/LightweightJava/ott-src/Makefile
thys/Sturm_Sequences/guide/Makefile

> The formal status of sessions is defined via "isabelle build" -- that is
> a powerful tool that can do many things. I.e. we can easily define that
> anything outside of it as outside of AFP.

This is the de-facto situation, yes.