Replace old index image with hub

Docker-DCO-1.1-Signed-off-by: Brian Goff <cpuguy83@gmail.com> (github: cpuguy83)
Fix more instances of "dotcloud/docker" in hack/ (and add a DOCKER_PKG environment variable to simplify references to our "package path" in our bundlescripts)

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Check for OS and root privileges in NewDaemon

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Move TMPDIR symlink cleanup to NewDaemon

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Move canonical root path detection to NewDaemon

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Move kernel version/capabilities detection to NewDaemon

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Move Server.ContainerAttach to Daemon.ContainerAttach

This is part of an effort to break apart the legacy server package. Help wanted!

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com>
New job "log": logs a new event

DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com>
Move "pause" to daemon/pause.go

This is part of an effort to break apart the deprecated server/ package

DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com>