Issue/25 move interface

Created by: edvgui

1. Added support for peer of interfaces (this allows to create movable interface with a real end in the container)
2. Added test case to reproduce the issue described in the ticket (moved interface raise a 404)
3. Fixed api, all operations on an interface will now reload the interface using the host the interface is in (this is not the original solution, this one is less generic and elegant but requires way less changes)

Closes #25 (closed)