Support now for being able list sub resources of a vnf. REST path is
/vnf/<vnf_id>/resources/. Resources will contain 'name', 'id', and
'type'.
APIImpact
Partial-Bug: 1602112
Change-Id: Ib9f0163c0c86df2a4d17630a5e6f7ca2d2fb22de
Signed-off-by: Tim Rozet <trozet@redhat.com>