Yarn: Release 1.0

[BYK]

• [x] Generate change log
• [x] Resolve https://github.com/yarnpkg/website/issues/372 (@BYK)
• [x] Tag 1.0
• [x] Add change log to blog post (@arcanis)
• [x] Publish to npm
• [x] Publish RPMs and MSIs
• [x] Document workspaces (@arcanis)
• [x] Document selective version resolutions (https://github.com/yarnpkg/website/issues/605) (@BYK)
• [x] Publish blog post
• [x] Publish blog post on website (@BYK)
• [x] Tweet the blog post (@cpojer)
• [x] Post on HN (@cpojer)
• [x] Monitor public channels for possible bug reports

[Daniel15]

The publishing (npm, RPMs, MSIs) is all automated based on tags, as long as the build succeeds.