Missing preview_url in appdesk and crud

The behaviour 'urlenhancer' added automatically the 'preview' button (in appdesk and crud), but the preview_url was not set.
Refactoring model properties cache
Adding lang config files
"Updating dictionaries"
DATE_FORMAT_DEFAULT pattern
Adding the item instance as parameter to 'show_when'
Added nosOnShow() inside wijexpander.afterExpand
Bugfix: don't save role on 'My account'
Only show 'refresh all metadata' for expert users
Preview inspector now takes disabled acions into account
Making div:hover CSS Wysiwyg style working in IE 10 (changed doctype to XHTML 1 Strict)
Bugfix translation (missing dictionary for common config)
"Updating French translations"
Regression : appdesk, switch view for grid principal
Bugfix : dialog multi-add in dialog queue
Bugfix : the widget not initialized on destroy bug, on wijmenu of appdesk
Bugfix: we can now detach a media using the provider
Appdesk : Little rewrite code for radio view
Bugfix : z-index pb in appdesk when dialog up his own z-index
Merge branch 'rel/0.2.1' of git://github.com/novius-os/core into rel/0.2.1