BigSwitch: Watchdog thread start after servers

Start the watchdog thread after the servers have
been initialized.

Closes-Bug: #1293799
Change-Id: Ic7ae1f55bd7faed6edde84d9d0b52fc8fe7a1fc1
Add session persistence support for NVP advanced LBaaS

Change-Id: I2042894755cdaf54b2bc39e58028746aa7c1e8ea
Closes-Bug: #1256243
Merge "BigSwitch: Watchdog thread start after servers"
Merge "Add session persistence support for NVP advanced LBaaS"