* cmd/clef: add newaccount command

* cmd/clef: document clef_New, update API versioning

* Update cmd/clef/intapi_changelog.md

Co-Authored-By: ligi <ligi@ligi.de>

* Update signer/core/uiapi.go

Co-Authored-By: ligi <ligi@ligi.de>

Co-authored-by: ligi <ligi@ligi.de>