OO-1819: add param for inital author, add param to not set the initial author, return more infos for course members

OO-1785: revert order of first name and last name, make not mandatory property visible but not by default

OO-1770, OO-1769: allow pseudonym and guest posts, refactor the message model to hold only threads or messages of a unique thread in memory, minimize the number of joins on query, minimize the number of queries on peekview, remove buggy docking feature...

OO-1741 remove ? from dummy avatar images, adding anonymous avatar and removing old avatar images outside the theme

OO-1739: backport the delete button in file element and use it in user profil for the avatar, in the resource description and in the catalog entry editor

OO-1635,OO-722: refactor the ajax by iframe to use XHR, push the current business path to the browser via HTML5 push state, implements back button support via HTML5 History API...

OO-1645,OO-1595: refactor the personal configuration of calendars, the datamodel of imported calendars, make the description visible and editable...

OO-1606: close asap the database connection in the QTIPreWarm executor, remove some unused spring dependencies as Eclipse Mars detect them

OO-1567: hardened the user name's cache against null, show a string as author if the feed author user name is null

OO-1561 replace lang parameter in pwd change and registration email with language parameter to not collide with html entity ⟨

OO-1536: inline the user's visiting card in the different member list, add a tool in the list as in author list, add close button for the visinting card (if opened in the main window), add close button to the business groups tabs

OO-1541: select the user in the username column and the the next 2, action column now opens the visiting card, fix some wording issues

OO-1483: implement a prewarm infrastructure to warm-up openolat caches, implement it for velocity templates, display names of users and QTI 2.1 resources