Add mention about Keycloak bootstrap tasks

<tsegismont> pilhuhn, jpkroehling BTW, shouldn't we add to the docs that after install, an admin user should be created?
<jpkroehling> tsegismont, users can be created only via localhost
<jpkroehling> admin users, that is
<jpkroehling> tsegismont, http://snag.gy/fvIpz.jpg
<jbossbot> Title: snaggy - paste images!
<jpkroehling> tsegismont, would that be enough ?
<tsegismont> jpkroehling, IANASECC
<tsegismont>
<tsegismont> I Am Not A SECurity Consultant
<jpkroehling> well, I'd say that if an user can access "localhost", or the shell to the machine, this user is indeed allowed to create an user
<jpkroehling> no matter if the user was the one who set Hawkular first
<jpkroehling> we could indeed add a hint to the docs, though
<jpkroehling> like, "Don't forget to also perform the bootstrap tasks for Keycloak, such as setting up an admin user"
<tsegismont> +1