Automate most of the release process

[jeanlaurent]

This automate the release process.

Current Status :

• Version Bump
• Compile & Generate Binaries
• Tag
• Create release on github
• Push binaries to release page
• Generate Checksums
• Add Installation Instructions
• Add Release Notes
• Generate and Add Contributor List
• Update the CHANGELOG.md
• Update the Documentation
• Verify the Installation ( probably very hard to automate at 100% )
• Order wine ( not sure how to do this one )

This is ready to try for the v5.0.5 release.
Things to consider for improvment :

• Runs everything ( not only the binary creation) in a container, so we don't rely on the local machine
• Do the final version bump back to dev automatically ( this needs to know the next version number
• Do not ask for the current version number since this can be done by carefully looking into version/version.go
• We could probably force push the docs branch but I'm not too familiar with the process, and prefer to live yet another release before doing it.

[nathanleclaire]

Won't this (use of emoji) cause issues if someone uses the script from Windows or Linux ? e.g. inside of a container

[nathanleclaire]

Looking like a good start. I posted some comments but this will be pretty useful once finished.

[jeanlaurent]

ready for review @docker/machine-maintainers

[dgageot]

LGTM

[dgageot]

Will use this on Monday for the release!

[dgageot]

Next step is to make it run in a container