[MRM-1737] Improve welcome page

git-svn-id: https://svn.apache.org/repos/asf/archiva/trunk@1428116 13f79535-47bb-0310-9956-ffa450edef68
i18n

git-svn-id: https://svn.apache.org/repos/asf/archiva/trunk@1428117 13f79535-47bb-0310-9956-ffa450edef68
logout display welcome

git-svn-id: https://svn.apache.org/repos/asf/archiva/trunk@1428118 13f79535-47bb-0310-9956-ffa450edef68