Add coordination section to the HA conf sample
Add coordination section to the HA conf sample

Add coordination section to the HA conf sample for the st2docs update to
include the Redis/Zookeeper requirement.

StackStorm/st2,Plexxi/st2,Plexxi/st2,StackStorm/st2,StackStorm/st2,nzlosh/st2,Plexxi/st2,StackStorm/st2,nzlosh/st2,Plexxi/st2,nzlosh/st2,nzlosh/st2