Fix dependencies for install_docker_engine state
Summary:
Strangely, on Equatower, pkg is executed before file
for the install_docker_engine state.
This change explicitly sets the order to use.
Test Plan: salt equatower state.apply roles/paas-docker/docker
Reviewers: dereckson
Reviewed By: dereckson
Differential Revision: https://devcentral.nasqueron.org/D1398