This commit addresses a few more frequently-asked questions:
* clarifies that bootstrapping doesn't happen even after a full cluster
restart.
* removes the example that uses IP addresses, to try and further encourage the
use of node names for bootstrapping.
* clarifies that auto-bootstrapping might form different clusters on different
hosts, and gives a process for starting again if this wasn't what you wanted.
* adds the "do not stop half-or-more of the master-eligible nodes" slogan that
was notably absent.
* reformats one of the console examples to a narrower width