release.nix: added extra steps
release.nix: added extra steps

svn path=/strategoxt/trunk/; revision=18752

metaborg/strategoxt,lichtemo/strategoxt,metaborg/strategoxt,lichtemo/strategoxt,lichtemo/strategoxt,Apanatshka/strategoxt,metaborg/strategoxt,lichtemo/strategoxt,Apanatshka/strategoxt,Apanatshka/strategoxt,lichtemo/strategoxt,metaborg/strategoxt,Apanatshka/strategoxt,metaborg/strategoxt,Apanatshka/strategoxt