Dns stops working on precise when network manager is enabled

In Precise and Quantal, we nuke the dnsmasq launched by NetworkManager

Fixes LP# 993666

Change-Id: I4b39010765e2cbbea1ca3fc3120bf329015b7a56
Support a flag for setting Keystone Token backend

Fixes LP# 1073274

Change-Id: Ib4373a4a4d31e440e40f977f8f7ffa312f2d97be
Pick just the first route when looking for the host interface

The current code will fail miserably if multiple default routes are
present (perfectly normal if they have different metrics). Fixing
the code to pick the first/top entry

Fixes LP# 1084470

Change-Id: Ieda16b575685071ff831c92e6b2a29737d6f849b
Merge "Support a flag for setting Keystone Token backend"
Merge "Dns stops working on precise when network manager is enabled"
Merge "Pick just the first route when looking for the host interface"