Handle service creation race by service workers

This handle a race where a sibling has already created the service
record in the database.  This fix is similar to that of commit
f6c341b4.

Change-Id: I7975fc632eee34390c5d7dc275b52363ad45475e
Closes-bug: 1326901
Log when nova-conductor connection established

The current warning in wait_until_ready() is a bit of a red-herring.
When just looking at the logs, it's warning status may lead you to
believe the failure to connect to nova-conductor is fatal when really
it was retried and connected successfully.

The WARNING message on timeout is modified to clearly show that it is
retrying the connection.  A partner message is shown to inform that
the connection has been established.

Change-Id: I2040707df7caf8685c84c82ec9b8cc97cb04b47e
Updated from global requirements

Change-Id: Iaf117fa1ef752da09f2a0840baa9258dea9b3a61
Merge "Handle service creation race by service workers"
Merge "Updated from global requirements"
Merge "Log when nova-conductor connection established"