taxonomies and langs should be assets published with revisions

[alexgarel]

Currently when we release, we have to run build_tags_taxonomies.pl and build_lang.pl

Apart from loosing time at reales time and possibly running into complications, this is a bit risky if we want to rollback to a previous version.

It also makes it difficult to cleanup the github with taxonomies cache as we don't know which versions are the right one.

As we have done with javascript bundles, on release, we should export archives of sto files for lang and taxonomies for each flavor of the project, and add them as assets to the release.