Github-backup

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- Chore: drop Python 2.6. [Jose Diaz-Gonzalez]
- Feat: simplify release script. [Jose Diaz-Gonzalez]

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Fix
~~~
- Cleanup pep8 violations. [Jose Diaz-Gonzalez]

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- Add additional output for the current request. [Robin Gloster]

This is useful to have some progress indication for huge repositories.
- Add option to backup additional PR details. [Robin Gloster]

Some payload is only included when requesting a single pull request
- Mark string as binary in comparison for skip_existing. [Johannes
Bornhold]

Found out that the flag "--skip-existing" did not work out as expected on Python
3.6. Tracked it down to the comparison which has to be against a string of bytes
in Python3.

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- Add option to fetch followers/following JSON data. [Stephen Greene]

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- Short circuit gists backup process. [W. Harrison Wright]
- Formatting. [W. Harrison Wright]
- Add ability to backup gists. [W. Harrison Wright]

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- Change option to --all-starred. [W. Harrison Wright]
- JK don't update documentation. [W. Harrison Wright]
- Put starred clone repoistories under a new option. [W. Harrison
Wright]
- Add comment. [W. Harrison Wright]
- Add ability to clone starred repos. [W. Harrison Wright]