Release 0.0.57

Added

• GA_get_subaccount: add user_path, core_descriptor, slip132_extended_pubkey.
• GA_get_assets: add ability to fetch informations about Liquid assets by
  specifying one or more of the following fields: names, tickers, category.

Changed

• Singlesig: GA_convert_amount: If a fallback fiat rate is provided the
  function will return that rate immediately instead of waiting for the latest
  rate to be fetched.
• GA_refresh_assets: remove "refresh" parameter. Now every call to
  GA_refresh_assets will perform a network call to update the Liquid assets. To
  avoid the network call use GA_get_assets. In addition GA_refresh_assets now
  does not return any value, to get assets data use GA_get_assets.
• GA_get_assets: it is now possible to fetch informations via the assets_id
  even before logging into a session.
• Removed support for LiquiDEX v0 for GA_create_swap_transaction,
  GA_complete_swap_transaction and GA_validate, which now support LiquiDEX v1
  only. LiquiDEX v0 transactions can still be created and completed with
  GA_create_transaction.