EZP-23513: implement Expanding converter
EZP-23513: implement EmbedLinking converter
EZP-23513: remove CustomTags converter
EZP-23513: update Link converter to handle linked embeds
EZP-23513: update Embed converter for extraction of embed's link data
EZP-23513: simplify embedding added in #1059
EZP-23513: simplify core transformation stylesheet
EZP-23513: improve main converter tests
EZP-23513: update service configuration
EZP-23513: update compilation pass
EZP-23513: pass converted link parameters to Legacy  Stack