Doesn't find git repository. Fails without meaningful information to correct issue.

[recursion-ninja]

From this TravisCI build.

$ hpc-coveralls --coverage-mode=StrictlyFullLines --exclude-dir=bench --exclude-dir=test test-suite
fatal: Not a git repository (or any of the parent directories): .git
hpc-coveralls: readCreateProcess: git "rev-parse" "HEAD" (exit 128): failed

Doesn't provide information or suggestions to rectify the issue when failing.