PROBLEM: can't have value of 'export_macro' attribute (of class element) expanded using preprocessor macro
PROBLEM: can't have value of 'export_macro' attribute (of class element)
expanded using preprocessor macro

SOLUTION: add attribute 'export_header' to element 'class' in which the
macro can be defined.

c-rack/zproto,sphaero/zproto,jemc/zproto,jemc/zproto,sphaero/zproto,asokoloski/zproto,jdiez17/zproto,vyskocilm/zproto,jdiez17/zproto,c-rack/zproto,c-rack/zproto,c-rack/zproto,hintjens/zproto,bkmit/zproto,vyskocilm/zproto,jemc/zproto,zeromq/zproto,sappo/zproto,somdoron/zproto,hintjens/zproto,zeromq/zproto,bkmit/zproto,asokoloski/zproto,asokoloski/zproto,bkmit/zproto,jdiez17/zproto,bkmit/zproto,zeromq/zproto,sappo/zproto,vyskocilm/zproto,sappo/zproto,sphaero/zproto,vyskocilm/zproto,bkmit/zproto,jemc/zproto,jdiez17/zproto,jemc/zproto,jemc/zproto,vyskocilm/zproto,jdiez17/zproto,vyskocilm/zproto,hintjens/zproto,asokoloski/zproto,somdoron/zproto,zeromq/zproto,somdoron/zproto,jdiez17/zproto,zeromq/zproto,sappo/zproto,somdoron/zproto,asokoloski/zproto,somdoron/zproto,somdoron/zproto,sphaero/zproto,asokoloski/zproto,sappo/zproto,sphaero/zproto,jemc/zproto,sappo/zproto,hintjens/zproto,bkmit/zproto,hintjens/zproto,c-rack/zproto,jdiez17/zproto,asokoloski/zproto,zeromq/zproto,sappo/zproto,bkmit/zproto,c-rack/zproto,c-rack/zproto,somdoron/zproto,hintjens/zproto,zeromq/zproto,sphaero/zproto,hintjens/zproto,vyskocilm/zproto