n-acd - IPv4 Address Conflict Detection

CHANGES WITH 1:

        * Initial release of n-acd. This project implements the IPv4 Address
          Conflict Detection standard as defined in RFC-5227. The state machine
          is implemented in a shared library and provides a stable ISO-C11 API.
          The implementation is linux-only and relies heavily on the API
          behavior of recent linux kernel releases.

        * Compared to the pre-releases, this release supports many parallel
          probes on a single n-acd context. This reduces the number of
          allocated network resources to O(1), based on the number of running
          parallel probes.

        * The n-acd project is now dual-licensed: ASL-2.0 and LGPL-2.1+

        Contributions from: Beniamino Galvani, David Herrmann, Thomas Haller,
                            Tom Gundersen

        - Tübingen, 2018-08-08