In some cases it's needed to have a direct link "register" on website where JS adapter is used.
Therefore the JS API could be enriched by 'register' and 'createRegisterUrl' methods.
The implementation is quite easy since createLoginUrl already support this feature when passing option parameter 'action' = register.
Update docs as weel: http://keycloak.github.io/docs/userguide/html/ch08.html#d4e1098
The show case of these new API could be in js-console example: https://github.com/keycloak/keycloak/tree/master/examples/js-console