Test for save and load commands

Improve test for save to tar and load from tar commands.
Docker-DCO-1.1-Signed-off-by: Fabio Falci <fabiofalci@gmail.com> (github: fabiofalci)
Quote volume path to allow spaces

Docker-DCO-1.1-Signed-off-by: Travis Cline <travis.cline@gmail.com> (github: tmc)
docker-ci 0.5.6: Fully dockerize docker-ci. Add build test coverage. Add backup builder.

Docker-DCO-1.1-Signed-off-by: Daniel Mizyrycki <daniel@docker.com> (github: mzdaniel)
Merge pull request #4172 from fabiofalci/test_save_and_load

Test for save and load commands
Merge pull request #4185 from tmc/fix-building-with-space

Quote volume path in Makefile to allow spaces
Merge pull request #4163 from mzdaniel/docker-ci

docker-ci 0.5.6: Fully dockerize docker-ci. Add build test coverage. Add backup builder.