Merge pull request #8 from MSOpenTech/host-management

Fix azure sdk import in azure host driver.
replace os/user with go-homedir

os/user can't be used in cross-platform builds, hence we vendor a
cross-platform hack.

Signed-off-by: Peter Salvatore <peter@psftw.com>
Merge pull request #9 from psftw/host-management

replace os/user with go-homedir