fix(CONTRIBUTING): Developer Certificate of Origin w/o Grant

In 7fb55f77250a9b52b0515a7e655ecc605ae452ca the DCO lost the grant so
change the title back to just DCO.

Docker-DCO-1.1-Signed-off-by: Brandon Philips <brandon.philips@coreos.com> (github: philips)
Swap Firefox to Iceweasel so that the Desktop Integration example is simplified and easier to understand

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Adjust test to match its comment

Docker-DCO-1.1-Signed-off-by: Andrew Williams <williams.andrew@gmail.com> (github: TheDude05)
Add better ".git" detection and use

This way, packagers can set GIT_DIR appropriately if they'd prefer to not have ".git" inside their working directory.

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

Shutdown contains debug warnings like:

[debug] deviceset.go:699 [deviceset docker-0:33-17945897] waitRemove(/dev/mapper/docker-0:33-17945897-pool)
[debug] deviceset.go:380 libdevmapper(3): libdm-common.c:552 (-1) Device /dev/mapper/docker-0:33-17945897-pool not found

This is because shutdown is using removeDeviceAndWait() to remove the pool device and the
wait part fails because the pool is gone.

We fix this by adding a pool specific removal function which avoids all the trickiness of the
normal remove.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
devmapper: Remove byHash hack

We no longer pass "pool" anywhere that uses byHash() per the last
commit, so we can now remove this hack.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
Fix bogus variable reference in mkimage-yum.sh

Fixes this: https://github.com/dotcloud/docker/commit/d419da7227826e84e9375ece4fd9d4978a42cbf7#commitcomment-5344982

Docker-DCO-1.1-Signed-off-by: Chris St. Pierre <chris.a.st.pierre@gmail.com> (github: stpierre)
Avoid extra mount/unmount during build

CmdRun() calls first run() and then wait() to wait for it to exit,
then it runs commit(). The run command will mount the container and
the container exiting will unmount it. Then the commit will
immediately mount it again to do a diff.

This seems minor, but this is actually problematic, as the Get/Put
pair will create a spurious mount/unmount cycle that is not needed and
slows things down. Additionally it will create a supurious
devicemapper activate/deactivate cycle that causes races with udev as
seen in https://github.com/dotcloud/docker/issues/4036.

To ensure that we only unmount once we split up run() into create()
and run() and reference the mount until after the commit().

With this change docker build on devicemapper is now race-free, and
slightly faster.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
add error to docekr build --rm

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
disallow tcp:// from defaulting to 127.0.0.1:4243

This stops docker from accepting tcp:// as a valid bind address.

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
Merge pull request #4043 from tianon/hack-git-detection-and-use

Add better ".git" detection and use
Add shasum fallback to hack/make/dynbinary for Darwin (where sha1sum is not available)

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Merge pull request #4096 from alexlarsson/fix-devmapper-race-2

Avoid extra mount/unmount during build
Image tag  endpoint doc typo.

Docker-DCO-1.1-Signed-off-by: Pedro Dias <petermdias@gmail.com> (github: apocas)
remove unneeded sysctl changes in sysvinit-redhat init script

Docker-DCO-1.1-Signed-off-by: Adam Miller <admiller@redhat.com> (github: maxamillion)
Merge pull request #4103 from vieux/add_error_build-rm

add error to docker build --rm
Merge pull request #4062 from alexlarsson/clean-shutdown

devmapper: Fix shutdown warnings
fix content-type for job.Stdout.Add

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
fix content-type for legacy

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
Merge pull request #4108 from unclejack/remove_default_tcp_bind_address

disallow tcp:// from defaulting to 127.0.0.1:4243