live555: 2018.02.12 -> 2018.02.28

Semi-automatic update generated by https://github.com/ryantm/nix-update tools. These checks were done:

- built on NixOS
- Warning: no binary found that responded to help or version flags. (This warning appears even if the package isn't expected to have binaries.)
- found 2018.02.28 with grep in /nix/store/gfv4ai63b95lkydlxj9579driy60h4v6-live555-2018.02.28
- found 2018.02.28 in filename of file in /nix/store/gfv4ai63b95lkydlxj9579driy60h4v6-live555-2018.02.28