Change: Refactor OcAvatarGroup and rename to OcAvatars

We've added more share types for the OcAvatars and refactored
the components used, also we removed the expand animation when focused
or hovered.

https://github.com/owncloud/web/issues/5736
https://github.com/owncloud/owncloud-design-system/pull/1614
https://github.com/owncloud/owncloud-design-system/pull/1639
