accordion: widgets and templates
Merge tracking branch 'infopark/develop' into feature/accordion
accordion widget generators
adds view to accordion generator
updates generator to include CSS and spec for AccordionWidget
generators for accordion panels
+ css definitions for nested accordion widget
accordion widget: simplify valid_widget_classes method
generator: accordion panel is invoked by the accordion generator
Merge branch 'release/release-20131112' into develop

* release/release-20131112:
  bump version to 4.0.0
bugfix: exchange infopark.refresh and remove .hide class

fixes #234
technical implementation to display a progress bar for uploaded files

+ design missing
bugfix: spinner did not disappear after delete operation was finished

fixes #235
bugfix: main yield was not intended correctly

fixes #221
bugfix: handle ESC key so that it is not propagated to the edit view

fixes #210
update changelog
bugfix: slideshare widget generator tried to copy a non-existing folder

fixes #238
update test app gems
bugfix: resource container class was not defined correctly
extend search page and remove search cell

fixes #233
bugfix: in case no homepage found still display a 404 page