The previous commit used the wrong URL for a private repo. This was
masked by the lack of error loging in logging_subprocess (which will be
in a separate branch)
Back up reporitory pull requests by passing the --include-pulls
argument. Pull requests are saved to
repositories/<repository name>/pulls/<pull request number>.json. Include
the --pull-request-comments argument to add review comments to the pull
request backup and pass the --pull-request-commits argument to add
commits to the pull request backup.
Pull requests are automatically backed up when the --all argument is
uesd.
Pass the -H or --github-host argument with a GitHub Enterprise hostname
to backup from that GitHub enterprise host. If no argument is passed
then back up from github.com.