Fix false positives wrt attribute initialisers w/o constructor

The presence of a constructor (or destructor) was checked inside a block
that was only entered when tracelevel > 0.
Move the checks out of that block to prevent false positives.
debian/control: Removed the dependencies upon wx2.8
regenerate_all.sh: Use 'git describe' to label current version
build_all.sh: 'make -j6' to speed up the build.
genmakeinst.sh: regenerate / make / install packages