Add the ability to attach remotely to a container

Also, you can now podman-remote run -it.  There are some bugs that need
to be ironed out but I would prefer to merge this so we can make both
progress on start and exec as well as the bugs.

* when doing podman-remote run -it foo /bin/bash, you have to press
enter to get the prompt to display. with the localized podman, we had to
teach it connect to the console first and then start the container so we
did not miss anything.

* when executing "exit" in the console, we get a hard lockup likely
because nobody knows what to do.

* custom detach keys are not supported

* podman-remote run -it alpine ls does not currently work.  only
dropping to a shell works.

Signed-off-by: baude <bbaude@redhat.com>

cmd/podman/commands.go

@@ -11,7 +11,6 @@ const remoteclient = false
 // Commands that the local client implements
 func getMainCommands() []*cobra.Command {
 	rootCommands := []*cobra.Command{
-		_attachCommand,
 		_commitCommand,
 		_execCommand,
 		_generateCommand,
@@ -47,7 +46,6 @@ func getImageSubCommands() []*cobra.Command {
 func getContainerSubCommands() []*cobra.Command {
 
 	return []*cobra.Command{
-		_attachCommand,
 		_checkpointCommand,
 		_cleanupCommand,
 		_commitCommand,