Enhancement: Add share indicator for direct and indirect shares in file list

We've added the ability for the user to directly see whether a resource is shared in the file list.
For this, share indicators in the form of a group icon and link icon will appear in a new column near the shared resource.
The blue color of an icon tells whether outgoing shares exist directly on the resource.
The grey color of an icon tells that incoming or outgoing shares exist on any of the parent folders.

https://github.com/owncloud/web/issues/2060
https://github.com/owncloud/web/issues/2894
https://github.com/owncloud/web/pull/2877

