Add utilities to test tap interface networks

Add an ArpResponder based on a generic PacketResponder class, and a
TestHttpServer based on NanoHttpd.

Test: tests based on these utilities
Bug: 160617623
Bug: 160656765
Change-Id: I50b872a8b23e8df997e8f62f0adc7c0256c4d74d
4 files changed
tree: a24bfeae661a92c65dd33944e75bec3934501ec8
  1. staticlibs/