Avoid failure when Connect is under maintenance on some modules

Most of packages tests have been modified to retrieve Nuxeo packages from maven dependencies (Nexus) instead of Connect to avoid dependency to a particular deployment server.

Packages that do not rely on this stratefgy fail when Connect is down (under maintenance for instance), they should be updated:

Example at https://qa.nuxeo.org/jenkins/job/master/job/addons_FT_nuxeo-platform-lang-ext-incomplete-master/80/consoleText, see addons_FT_nuxeo-platform-lang-ext-incomplete-master-80-console.txt

(mentioning nuxeo-jsf-ui package instead of retrieving it from nexus): https://github.com/nuxeo/marketplace-lang-ext-incomplete/blob/master/ftest/webdriver/itests.xml#L13

<property name="mp.install" value="nuxeo-jsf-ui,file:${out.dir}/marketplace-lang-ext-incomplete-${maven.project.version}.zip" />

Detected failures while Connect under maintenance on:

• https://qa.nuxeo.org/jenkins/job/master/job/addons_FT_nuxeo-platform-lang-ext-incomplete-master/
• https://qa.nuxeo.org/jenkins/job/master/job/plugins_nuxeo-timeoff-master-master/
• https://qa.nuxeo.org/jenkins/job/master/job/FT-nuxeo-drive-master-linux
• https://qa.nuxeo.org/jenkins/job/master/job/FT-nuxeo-drive-master-windows/
• https://qa.nuxeo.org/jenkins/job/master/job/FT-nuxeo-master-bench-drive-tomcat