Enhancement: Redesign link sharing

We have redesigned the public link list in the right sidebar. Links now can be edited in-line and have a similiar look-and-feel to people and group shares.
Additionally, creating new links now is less cumbersome and the default name, while not configurable from the backend anymore, is now translated.

https://github.com/owncloud/web/pull/6749
https://github.com/owncloud/web/pull/6885
https://github.com/owncloud/web/pull/6961
https://github.com/owncloud/web/issues/7149
https://github.com/owncloud/web/pull/7150
