Add --scheduler option in manage command in order to prepare pluggable schedulers

Signed-off-by: Francis Bouvier <francis.bouvier@gmail.com>
Update test to new Scheduler interface

Signed-off-by: Francis Bouvier <francis.bouvier@gmail.com>
Add --scheduler-option

Signed-off-by: Francis Bouvier <francis.bouvier@gmail.com>
Add Node.Container method to retrieve a container from it's ID

Signed-off-by: Francis Bouvier <francis.bouvier@gmail.com>
Add ApiScheduler

Signed-off-by: Francis Bouvier <francis.bouvier@gmail.com>
Merging master (move --filter in --scheduler-option)

Signed-off-by: Francis Bouvier <francis.bouvier@gmail.com>