Custom Authorities - Create/Update/Delete

[grctest]

https://github.com/BTS-CM/beet-deeplinks/blob/main/examples/BTS/054_custom_authority_create.js
https://github.com/BTS-CM/beet-deeplinks/blob/main/examples/BTS/055_custom_authority_update.js
https://github.com/BTS-CM/beet-deeplinks/blob/main/examples/BTS/056_custom_authority_delete.js
https://github.com/bitshares/bitshares-core/blob/b92b82ba3e57381d111f28383e8cfa89a8356966/libraries/protocol/include/graphene/protocol/custom_authority.hpp#L36

[grctest]

Will be included in the latest version.