Fix odd issues with "make docs", add "make docs-shell", and canonicalize our docs Dockerfile a bit more

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
fix doc, load and get

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
Merge pull request #3593 from dotcloud/fix_doc

fix doc, load and get
Merge pull request #3598 from tianon/fix-vieux-docs-errors-again

Fix odd issues with "make docs", add "make docs-shell", and canonicalize...
move viz to a job

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
update TODO

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
Merge pull request #3613 from vieux/deprecated_viz_job

move viz to a job
move copy to a job

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
Merge pull request #3560 from vieux/copy_job

move copy to a job