Pin safety to latest version 1.5.1

[pyup-bot]

safety is not pinned to a specific version.

I'm pinning it to the latest version 1.5.1 for now.

These links might come in handy: PyPI | Changelog | Repo

Changelog

1.5.1

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• Fixed an error on unpinned VCS requirements. This is a regression, see AttributeError: 'Requirement' object has no attribute 'project_name' for VCS requirements pyupio/safety#72

1.5.0

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• Internal refactoring. Removed dependency on setuptools and switched to the new dparse library.

1.4.1

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• Fixed a bug where absence of stty was causing a traceback in safety check on Python 2.7 for Windows.

1.4.0

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• Added the ability to ignore one (or multiple) vulnerabilities by ID via the --ignore/-i flag.

1.3.0

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• Added --bare output format.
• Added a couple of help text to the command line interface.
• Fixed a bug that caused requirement files with unpinned dependencies to fail when using
  a recent setuptools release.

1.2.0

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• Added JSON as an output format. Use it with the --json flag. Thanks Stype.

1.1.1

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• Fixed terminal size detection when fed via stdin.

1.1.0

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• Compatibility release. Safety should now run on macOs, Linux and Windows with Python 2.7, 3.3-3.6.
  Python 2.6 support is available on a best-effort basis on Linux.

1.0.2

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• Fixed another error on Python 2. The fallback function for get_terminal_size wasn't working correctly.

1.0.1

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• Fixed an error on Python 2, FileNotFoundError was introduced in Python 3.

1.0.0

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• Added terminal size detection. Terminals with fewer than 80 columns should now display nicer reports.
• Added an option to load the database from the filesystem or a mirror that's reachable via http(s).
  This can be done by using the --db flag.
• Added an API Key option that uses pyup.io's vulnerability database.
• Added an option to cache the database locally for 2 hours. The default still is to not use the cache. Use the --cache flag.

0.6.0

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• Made the requirements parser more robust. The parser should no longer fail on editable requirements
  and requirements that are supplied by package URL.
• Running safety requires setuptools >= 16

0.5.1

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• Fixed a bug where not all requirement files were read correctly.

0.5.0

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• Added option to read requirements from files.

0.4.0

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• Filter out non-requirements when reading from stdin.

0.3.0

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• Added option to read from stdin.

0.2.2

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• Fix import errors on python 2.6 and 2.7.

0.2.1

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• Fix packaging bug.

0.2.0

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• Releasing first prototype.

0.1.0

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• First release on PyPI.

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖