Unittest
Add tests for re6setnet, slapos!1165 (closed) use this to run test on test-node.
tests contain 2 parts: unittest and network simulate test
-unittest: contain test for RegistryServer, RegistryClient, cli.conf, tunnel.BaseTunnelManger, tunnel.MultGatewayManager https://lab.nexedi.com/zf.huang/re6stnet/commit/e7636b866e846fda021a4874eb28883628eff05a
-net_test: use nemu to create net namespaces and run registry or node in each net ns, finally use ping to test ipv6 connectivty https://lab.nexedi.com/zf.huang/re6stnet/commit/5bc6419cca9b52a60f08b5bb75707d5ea7c99576