TUP-2403: refactor the packages for core.ui plugin.
TUP-2403: refactor for commons.ui.runtime plugin.
TUP-2403: refactor for metadata.managment plugin.
TUP-2403: refactor for metadata.managment.ui plugin.
TUP-2403: refactor for model plugin.
TUP-2403: refactor for registration plugin.
Merge branch 'feature/6.0/TUP-2403_refactor_package'
Merge pull request #19 from ggu-talend/master

TUP-2403: refactor the duplicated packages.