Implementation of checks UI for Jenkins CI servers

This plugin registers a ChecksProvider with the Gerrit UI that will fetch build results for a change from configured Jenkins servers and provide them to the checks panel in a change screen.

Limitations

Currently, only multibranch-pipeline jobs using the Gerrit SCM-source provided by the link:https://plugins.jenkins.io/gerrit-code-review/[gerrit-code-review]- plugin are supported.

The Jenkins Remote Access API does not provide all the information that could be displayed in Gerrit, e.g. a result summary. Thus, as of now, this plugin does not make full use of the checks API. As of right now, it will display the following data in the UI:

• Builds for the selected patchset including previous attempts
• Status of the build
• Result of the build
• Link to the build and its logs
• A result summary stating the result category used by the CI (e.g. Result: UNSTABLE)