Packageurl-python

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- Upgrade virtualenv.pyz to latest version 85
- Replace Travis CI by GitHub Actions 84
- Add black to the CI and apply formatting on whole codebase 91
- Improve url2purl support for nom URLs
- Improve url2purl support for rubygems.org URLs 89

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- Update version to be semver compliant. No changes to the code have been made.

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- Fix generic sourceforge PackageURL generation 79

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- Do not create a generic PackageURL for URLs without a path in url2purl 72
- Use project name as the Package name when creating generic sourceforge PackageURLs 74
- Update PyPI route pattern in url2purl to handle different file name formats 76
- Create generic PackageURL for code.google.com archive URLs 78
- Capture more download types for bitbucket URLs

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- Create a generic PackageURL for URLs that do not fit existing routes in url2purl 68

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- Drop support for Python 2 61
- Add support for new github URLs in url2purl 47