Robinhood not authenticating

[John Murphy]

Robinhood.auth_token() is returning undefined

it appears Robinhood may have changed the authentication api as this request is returning 404...

curl -v https://api.robinhood.com/api-token-auth/ \
   -H "Accept: application/json" \
   -d "username={username}&password={password}"

(taken from https://github.com/sanko/Robinhood/blob/master/Authentication.md#logging-in)