chirp: 20180614 -> 20180623

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools.

This update was made based on information from https://repology.org/metapackage/chirp-daily/versions.

These checks were done:

- built on NixOS
- Warning: no invocation of /nix/store/xbvizy0v1vv4ckgmjirl4f1q1dzl5scw-chirp-daily-20180623/bin/.chirpw-wrapped had a zero exit code or showed the expected version
- Warning: no invocation of /nix/store/xbvizy0v1vv4ckgmjirl4f1q1dzl5scw-chirp-daily-20180623/bin/chirpw had a zero exit code or showed the expected version
- 0 of 2 passed binary check by having a zero exit code.
- 0 of 2 passed binary check by having the new version present in output.
- found 20180623 with grep in /nix/store/xbvizy0v1vv4ckgmjirl4f1q1dzl5scw-chirp-daily-20180623
- directory tree listing: https://gist.github.com/055e2b6f2968f12fbdac11ac482d1878
- du listing: https://gist.github.com/a67d26089115a9a427073485eed6e931