Bump version to 1.2.1, update CHANGELOG.md

Bump version to 1.2.0, update CHANGELOG.md

Bump version to 1.1.0, update CHANGELOG.md

Bump version to 1.0.0, update CHANGELOG.md

Merge pull request PowerShell#433 from daviwil/release/0.12.1

Release 0.12.1

Merge pull request PowerShell#415 from daviwil/release/0.12.0

Release 0.12.0

Merge pull request PowerShell#402 from daviwil/release/0.11.0

Release 0.11.0

Merge pull request PowerShell#379 from PowerShell/release/0.10.0

Release 0.10.0

Update version in appveyor.yml

Merge pull request PowerShell#231 from PowerShell/release/0.6.1

Prepare 0.6.1 release