Flesh out LBaaS Workflow example

Add info on how to find subnet ID, available options
for flags used and some optional flags I feel are important
(--connection-limit and --session-persistence).

Also made some formatting changes to improve readablity.

Change-Id: I35e1d441c5eb4db3db49c520c8f1167e7348d7a5
Closes-Bug: #1221739
Merge "Flesh out LBaaS Workflow example"