Log methods using rpc communcation

In Icehouse was used rpc library from oslo-incubator. Because the code
wasn't mature enough it was running in DEBUG mode. After migrating to
oslo.messaging we don't need to have debug level in oslo.messaging but
it's good to have communication logged.

Closes-Bug: #1340696
Change-Id: I4f68545053912f96affc1bbcd64fcd7efe8d18c0
Correct misspelled variable name

In neutron/services/loadbalancer/drivers/embrane/driver.py,
"persistence" is wrote with an "a", not with an "e".
This patch fix this.

Change-Id: I8da0d6d28c188c73ed844a8a0c7a523dae713344
Merge "Correct misspelled variable name"
Merge "Log methods using rpc communcation"