The production env seems to use a newer spack repo state → log4cxx is
newer than currently supported for BrainScaleS → quickfix: pin to old
version.

This is a hack to enforce a reinstallation of meta-brainscales.
(The underlying problem is that pynn-brainscales does not specify all
the dependencies but only via meta-brainscales; and there's already one
installed and spack does not easily install another one ;).)

Add specs in spack.yaml. Update names for pyaescrypt and formencode and specify them as dependencies for tvb-framework.