Merge changes I608c9974,Ic13456c5,Ie77b1591 am: 61205df5b4
am: dadbfba71f

* commit 'dadbfba71f0edd79c4a9d2e48c0fcc7253c0e2ea':
  Support nested structs in CStruct.
  Move common netlink code into a new netlink.py
  Move the forwarding crash test to a new file.