To Command txt export: fix for cards without distributor

fix sell export error "string indices must be integers, not str"

fixes https://sentry.io/vindarel/abelujo/issues/554040094/

update datasources, html5lib==1.0b8 fix CI

gitlab-ci: build only on new tag pushed, not at every commit

Stock search: export as txt

fixes #48 - Export My Stock search results