OO-1440: use callout for filters and sorts of flexi tables and tables, missing i18n key for checklist in archive, fix 2x escaping in the group list of assessment tool, fix floating image in test statistics which breaks layout

OO-1446: set expiration date for versioned static file ( and transparent.gif ), refactor Workbook media resource to work without temporary files, add flag to media resources to accept or not ranges, add patch for Tomcat 8 ( thanks D. Haag )

OO-1254,OO-732: fix default template in certificate settings, wording, english translation, fix breadcrumb in the efficiency statement user tool

OO-936: implements course element "check list", enhance the flexi-table with sort, filter and export, enhance publish process with an update step, upgrade pdfbox to version 1.84

OO-763: don't use the container as reference for collection of components but an interface instead, break the inheritence of Panel and flatted it

OO-911, OO-912: implements the course node triggered buttons in assessment tool, implement bulk upload for tasks with selection of a group if needed

OO-852: implements the new bulk assessment wizard, move the task executor and scheduler in the services package

OO-622,CL-225: remove username from GUI in place where is not really needed and students can see it. Mark others place with //TODO username where it need more works and/or the username is only visible by author/coach/admin... Additional fix the setup sql for MySQL (index too long).