DeleteSliceFromNodes: check that slice is local (like AddSliceToNodes does)
DeleteSliceFromNodes: check that slice is local (like AddSliceToNodes does)

dreibh/planetlab-lxc-plcapi,dreibh/planetlab-lxc-plcapi,dreibh/planetlab-lxc-plcapi,dreibh/planetlab-lxc-plcapi