OO-203: refactor the ImageHelper to use different implementation, add an implementation based on ImageMagick/GhostScript for pictures and PDFs thumbnailing

FXOLAT-426 : remove LDAPAdminExtension class, add genericActionExtension (for SysAdminController) in ldapContext.xml. (according to the other modules)

FXOLAT-357: implements link abonnement to assessment tool, upgrade the publisher with the right business path

OO-183: if there is nothing to translate, don't show the translation panel. I don't see a better way to handle the issue for the moment.

OO-184 :  TOC controller and ChangelogController are not re-instantiated each time the user switches Tabs (pages) within an eportfolio map. Improved the subscriptionItem "jump to epMapPage" from within changelog tab.

OO-137 : refactor the textboxlistcomponent. this also contains a change in FormBasicController !  test carefully!

OO-1 : adjust memberslist coursenode css.  minor fixes : titlewrapper info-icon in courserun (single page)

OO-191 : check for passed null-value in EPNotificationsHandler (sometimes notifNewsController passes null ...)

OO-186 : extend Tunneling Request:  also send OpenOLAT user - local IP-Address within request-headers

--HG--
branch : 80-patch

--HG--
branch : 80-patch

--HG--
branch : 80-patch

OO-181 : replace the extWindow with the legacy OLAT ModalDialog in Link-Artefact-Workflow (this is a workaround to prevent JS exception described in OO-113). I also removed some dead code (private methods that are not called...)

--HG--
branch : 80-patch

OO-112 : fix wiki export via REST. ( removed group-wiki export. implement separately). Fixed a bug while exporting wiki to CP, if export-directory does not exist.

--HG--
branch : 80-patch

--HG--
branch : 80-patch

--HG--
branch : 80-patch

--HG--
branch : 80-patch