OO-213: make OpenOLAT more robust against corrupted course, mark them in details view, make home resistant to corrupted courses, give the possibility to delete them

OO-208: offer to download only the attached file and not a generic Mapper (there is only one file to download)

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branch : i18n_OO

FXOLAT-437:  don't delete efficiency statements of existent course, delete all UserCourseInfos before deleting the repository entry

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branch : i18n_OO

OO-204: refactor the DisplayPortraitManager to allow portrait saved in PNG and using the new ImageHelper implementation

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

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

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

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

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branch : 80-patch

OO-144: make possible to check only the visible length of string without subtle encoding issues (which are only databse relevant)

OO-170: refactoring of the property table, move efficiency statements and initial/recent launch dates to their own table

--HG--
branch : 80-patch

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branch : 80-patch

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branch : 80-patch

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branch : 80-patch