[emc,symcli] move symcli collection into its own plugin.

Related: #257.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
[emc,navicl] move navicli collection into its own plugin.

Related: #257.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
[emc,powerpath] move PowerPath collection into its own plugin

Move PowerPath functionality into a new powerpath plugin and
remove the (now empty) EMC plugin.

Fixes: #257.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>