Update roadmap for v2.7.1

Update to latest v2.7.0 release

Merge pull request #400 from emilstahl/patch-2

Update for release v2.5.0

Merge pull request #343 from wp-cli/update-release-2-4-0

Update handbook for release v2.4.0

Update to v2.3.0

Update roadmap.md

Merge pull request #268 from wp-cli/update-to-v2-1-0

Update to v2.1.0

Released v2.0.0

Merge pull request #206 from wp-cli/my-new-role

Update Daniel's relationship to the project