archive/tar: update to fix writing of PAX headers

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
Updated Red Hat Enterprise Linux installation instructions for version 7

Docker-DCO-1.1-Signed-off-by: Brian Exelbierd <bex@pobox.com> (github: bcexelbi)
Improve data volume container example.
Docker-DCO-1.1-Signed-off-by: Jason Livesay <ithkuil@gmail.com> (github: runvnc)
Fix a typo in the tutorial
docs/installation/google: update gcloud options

Docker-DCO-1.1-Signed-off-by: Johan Euphrosine <proppy@google.com> (github: proppy)
Joining registry maintainers

Docker-DCO-1.1-Signed-off-by: Olivier Gambier <olivier@docker.com> (github: dmp42)
Merge pull request #7146 from dmp42/master

Joining registry maintainers
Merge pull request #7078 from unclejack/fix_archive_tar_pax_headers

archive/tar: update to fix writing of PAX headers
Merge pull request #6569 from bcexelbi/rhel-install-update

Updated Red Hat Enterprise Linux installation instructions for version 7
Merge pull request #7030 from runvnc/patch-1

Better example for data container
Merge pull request #7112 from proppy/patch-8

docs/installation/google: update gcloud options
Merge pull request #7134 from MidnightDesign/patch-1

Fix a typo in the tutorial
pkg/units: Increased test coverage. Closes #7159.

Increased coverage:

  * Added test cases to size_test.go
  * Added coverage for duration.go

Docker-DCO-1.1-Signed-off-by: Francisco Carriedo <fcarriedo@gmail.com> (github: fcarriedo)
Merge pull request #7160 from fcarriedo/7159-test-coverage

pkg/units: Increased test coverage
add test

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)
reload links of parents when started

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

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)
update upon feedback and add test log

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)
add doc from @SvenDowideit

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

Docker-DCO-1.1-Signed-off-by: SvenDowideit <SvenDowideit@home.org.au> (github: vieux)