Stop ADD from following symlinks outside the context when passed as the first argument

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)

Docker-DCO-1.1-Signed-off-by: Tianon Gravi <admwiggin@gmail.com> (github: crosbymichael)
Fix "foo: no such file or directory" test failure, and normalize creation of custom error to always depend on if os.IsNotExist(err) so we don't hide other errors that might crop up in these tests

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)

Docker-DCO-1.1-Signed-off-by: Tianon Gravi <admwiggin@gmail.com> (github: crosbymichael)
Add remount for bind mounts in ro

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Use https to get the latest docker version

To avoid unexpected results since docker was using http.
For instance, my broadband doesn't return not found when it's down but
a html page saying that the internet is down. Docker was showing that
html instead of ignoring it.

Fix #3570

Docker-DCO-1.1-Signed-off-by: Fabio Falci <fabiofalci@gmail.com> (github: fabiofalci)

Docker-DCO-1.1-Signed-off-by: Fabio Falci <fabiofalci@gmail.com> (github: crosbymichael)
Add ca-certificates to our package Recommends

It's only in "Recommends" because it's only required for all but the esoteric configurations (since you can't "docker pull" from the index without it, but that's about it).

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)

Docker-DCO-1.1-Signed-off-by: Tianon Gravi <admwiggin@gmail.com> (github: crosbymichael)
Inline the test.docker.io fingerprint in the install.sh script as well

As long as we're doing it, we ought to do it for all the "official" Docker properties at least

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)

Docker-DCO-1.1-Signed-off-by: Tianon Gravi <admwiggin@gmail.com> (github: crosbymichael)
Add more specific lvm2 version to PACKAGERS document

I personally tested this using our container, and this was the lowest version that compiles and runs properly.

Docker-DCO-1.0-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)

Docker-DCO-1.1-Signed-off-by: Tianon Gravi <admwiggin@gmail.com> (github: crosbymichael)
Bump to version v0.7.6

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Merge pull request #3597 from crosbymichael/bump_v0.7.6

Bump to version v0.7.6