Enhanced apps management

TODO:
* [x] merge Handlebars.js pull request which this depends on https://github.com/owncloud/core/pull/10413
* [x] add »Recommended« tag to recommended apps (directly next to the score)
* [x] add link to »More apps in the store …«
* [x] sort by rating
* [x] meta category  »Recommended«
* [x] uninstall needs to be moved back in
* [ ] put the »Enable« button (including all the groups limit stuff) on the right
* [ ] restrict the height of the content to a few lines, allowing for it to be expanded
* [ ] fix alignment of rating stars. Maybe also make them SVG
* [ ] make it faster!