cpp: Do not close stdout/stderr when destroying EditInteractor
* lang/cpp/src/editinteractor.cpp (EditInteractor::Private): Initialize members 'state' and 'debug' in-class. Add member 'debugNeedsClosing'. (EditInteractor::Private::Private): Remove members initializers. Remember if 'debug' needs to be closed. (EditInteractor::Private::~Private): Only close 'debug' if it needs to be closed.
This fixes the problem that after destroying an edit interactor all
debug output went to /dev/null instead of stderr (or stdout) if one
enabled debugging of the edit interactors with GPGMEPP_INTERACTOR_DEBUG
set to stderr (or stdout).