function getSessionToken () {
  return dispatch => {
    dispatch(sessionTokenRequest())
    return appAuthToken.getSessionToken()

      .then((token) => {
        if (token) {
          dispatch(sessionTokenRequestSuccess(token))
          dispatch(logoutState())
          Actions.Tabbar()
        } else {
          dispatch(sessionTokenRequestFailure())
          Actions.InitialLoginForm()
        }
      })

      .catch((error) => {
        dispatch(sessionTokenRequestFailure(error))
        dispatch(loginState())
        Actions.InitialLoginForm()
      })
  }
}
## Token
If AppAuthToken has the sessionToken, the user is logged in
so set the state to logout.
Otherwise, the user will default to the login in screen.