Add support for SonarCloud

Add support for SonarCloud

If SonarCloud is used the old method is automatically disabled so that
Sonar is not run twice.

Example Usage:

- project:
    name: yangtools-sonar
    jobs:
      - gerrit-maven-sonar

    project: 'yangtools'
    project-name: 'yangtools'
    branch: 'master'
    mvn-settings: 'yangtools-settings'
    mvn-opts: '-Xmx1024m'
    sonarcloud: true
    sonarcloud-project-key: KEY
    sonarcloud-project-organization: ORGANIZATION
    sonarcloud-api-token: TOKEN

Issue: RELENG-1721
Change-Id: Ica1cd29bfc9246f2452370dd6ceb8b7e5b8e5329
Signed-off-by: Thanh Ha <thanh.ha@linuxfoundation.org>