Merge pull request #2577 from dotcloud/bump_v0.6.6

Bump v0.6.6
skip the volumes mounted when deleting the volumes of container.
use Binds key in hostConfig to detect volumes mounted from external.
Minor code simplification for Containers api
expunge the word 'Resource' in reference to a file/dir in a CONTAINER - that way users don't wonder how its different from a Path
add some common examples for docker images, and tell the user what -a filters out
make the docker commit help more copy&pasteable
Vagrantfile modified to support VBoxGuestAdditions_4.3.2
test: put each arg in a separate string

Each arg to docker run should be placed in a separate string.
Otherwise, when starting the command via exec.Cmd, the command is
interpreted as "echo test", which can't be found.
test: fix TestCreateStartRestartStopStartKillRm

cat needs stdin opened, otherwise it dies immediately.
test: skip TestCreate on Fedora due to lxc utils bug

In the dind environment running on a Fedora host, the lxc utils get
confused by the /sys/fs/cgroup/cpuacct,cpu cgroup mount and lxc-start
fails trying to access the wrong cgroup directory.
test: 2 second timeout (not 2000)
fix container restart race condition

Finish container cleanup before setting the state to stopped.
Otherwise, for an application that exits quickly, a call to Restart
can allow Start to be called again before cleanup is done, resulting in
overritten data in the Container struct.
test: fix TestRmi race condition
test: remove extra args in TestExitCode

The extra blank argument isn't needed and confuses libvirt.
Simplify the upstart example in host_integration.rst

Taking some pointers from @tianon on my pull request #2685.
Lintify code with confidence=1
Correct the quotations in the command to add the -r=false flag.  Thanks to @tianon for pointing this out.
Do ont truncate ID on docker rmi
fix layer size computation: handle hard links

This change makes docker compute layer size correctly.

The old code isn't taking hard links into account. Layers could
seem like they're up to 1-1.5x larger than they really were.