Use gzip compression in Ubuntu packages to make it at least possible to install on Lucid.

Docker-DCO-1.1-Signed-off-by: Evan Krall <krall@yelp.com> (github: EvanKrall)
Merge pull request #3543 from EvanKrall/gzip_debs

Use gzip compression in Ubuntu packages to make it possible to install on Lucid
move container_delete to job

handle error

remove useless errStr

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor@docker.com> (github: vieux)
Move restart to a job

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
Merge pull request #3476 from vieux/restart_job

Move restart to a job
Merge pull request #3180 from vieux/job_container_delete

Move container_delete to job
Move image_export to a job

Docker-DCO-1.0-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
Merge pull request #3490 from vieux/image_export_job

Move image_export to a job
Use '-s empty' instead of '-s dir'

This *should* have the same effect as the previous strategy: Instead of
'mkdir empty; fpm -s dir -C empty ...' we can simply do 'fpm -s empty'

Docker-DCO-1.1-Signed-off-by: Jordan Sissel <jls@semicomplete.com> (github: jordansissel)