NXP-15491: Make DM a transitional MP
NXP-15491: Deprecate DM; reorg directories
NXP-15491: update social-collaboration

Move OpenSocial resources to its MP
Make nuxeo-social-collaboration MP depend on nuxeo-opensocial
Merge branch 'feature-NXP-15491-make-DM-transitional-MP'

Rename artifacts:
- nuxeo-distribution-dm-selenium-tests to nuxeo-distribution-cap-selenium-tests
- org.nuxeo.tool:funkload-utility (nuxeo-distribution-dm/ftest/funkload) to nuxeo-distribution-cap-funkload-tests
- nuxeo-distribution-dm-cmis-tests to nuxeo-distribution-cap-cmis-tests

Remove artifacts:
- org.nuxeo.ecm.distribution:nuxeo-distribution-resources:zip:templates-common-dm
- org.nuxeo.ecm.distribution:nuxeo-distribution-dm

Folders reorg:
- nuxeo-distribution-cap/ftest/webdriver => nuxeo-distribution-cap-webdriver-tests
- nuxeo-distribution-dm/ftest/cmis => nuxeo-distribution-cap-cmis-tests
- nuxeo-distribution-dm/ftest/funkload => nuxeo-distribution-cap-funkload-tests
- nuxeo-distribution-dm/ftest/selenium => nuxeo-distribution-cap-selenium-tests
- nuxeo-distribution-dm/ftest/webdriver => nuxeo-distribution-cap-webdriver-tests
- nuxeo-distribution-social-collaboration/ftest/selenium => nuxeo-social-collaboration-selenium-tests