Fix issue when attaching stdin alone
Make DockerCli use its own stdin/out/err instead of the os.Std*
Make term function consistent with each other
Make NewDockerCli handle terminal
Implement regression test for stdin attach
TestKill and TestMultipleContainers: run sleep instead of cat /bin/zero. fixes #737
Add missing fprintf instead of printf
Merge pull request #1021 from errnoh/fix-test-filled-tmpfs

TestKill and TestMultipleContainers: run sleep instead of cat /bin/zero....
Merge pull request #1005 from dotcloud/1004-stdin_piping-fix

- Runtime: Fix issue when attaching stdin alone