Add note regarding quoting values for network.host
Add note regarding quoting values for network.host

Values for the network.host setting can often contain a colon which is a
character that is considered special by YAML (these arise in IPv6
addresses and some of the special tags like ":ipv4"). As such, these
values need to be quoted or a YAML parser will be unhappy with
them. This commit adds a note to the docs regarding this.

vroyer/elassandra,strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,vroyer/elassandra,vroyer/elassandra