Update code example on module page.

The example on the module page is not working at my installation. I needed to remove user to get a correct working link.

This is working at my installation.

Replace

  $login_link = ctools_modal_text_button(t('Modal Login'), 'modal_forms/nojs/user/login', t('Login via modal'),  'ctools-modal-modal-popup-small');

with

  $login_link = ctools_modal_text_button(t('Modal Login'), 'modal_forms/nojs/login', t('Login via modal'),  'ctools-modal-modal-popup-small');

Or is something wrong on my side?