Bug#842515: github-backup: FTBFS with newer directory

[Clint Adams]

Package: github-backup
Version: 1.20160522-1
Severity: serious

Because we've updated GHC to 8.0, the version of the directory library
has also been updated, and you'll need something like
https://github.com/joeyh/github-backup/commit/848f6b64f75f4d267ba364405fb2a7b284969020