Add fake for fileMover
Add fake for fileMover

[#128789021](https://www.pivotaltracker.com/story/show/128789021)

Signed-off-by: Zachary Auerbach <84a275e6a279738f2aa78daf0002615dee69cc28@pivotal.io>

cloudfoundry/bosh-utils,cloudfoundry/bosh-utils