Do 0.2.0 release

[cornelius]

This is the checklist for things to do when doing the next release, which is 0.2.0. It will be done when the work for the 0.2 milestone is completed.

• Adapt the version number of the client to "0.2.0"
• Update changelog
• Generate man pages
• Tag the git repository with v0.2.0
• Add release notes on the GitHub release page and mark release as pre-release