Update share action text to display owner/recipients

- when a share was changed, update the share action text
- added file data attribute "data-share-recipients"
Added unit tests for share.js and share icon
change shared folder icon to use share icon instead of people
More unit tests and fixes for share
Now using shareOwner for the share owner

Makes it consistent with the regular file list fileData
let file cache handle the versions size
return size '0' if the trashbin folder doesn't exists yet
use OC_DB::dropTable()
minimal mail template editor for administrators, refs #7177
Multiple fixes to sharing overview

- scrolling to next page now correctly renders share icons
- reshareing/unsharing a reshare will now still keep "Shared by" label
convert mail template editor to app framework for a restful api
Fix merge conflict
Use recipient display names when updating shares in the UI

Since OC.Share didn't have any array containing the list of shares for
the current file, OC.Share.currentShares has been introduced to contain
the full share item structure instead of the reduced one
OC.Share.itemShares.

The event "sharesChanged" is now passing OC.Share.currentShares, which
itself includes the display name to be displayed for the recipients in
the action icon.
Do not update action icon recipients for file list

Since the files app doesn't have the recipient information on load it
cannot initially render the recipients in the action icons.

For this reason the action icon will not be updated with the recipients
after changing the shares, for consistency.
Added "Shared with link" sidebar section in files app

Added section to only show link shares.

Please note that the filtering is currently done on the client side
which might not be the most efficient way of doing it.
Fix mime type returning for "shared with others" files

Use "path" instead of "file_target", as the latter is not always set /
reliable.
Fixed wording to "Shared by link"
Upgrade SabreDAV to 1.8.10
Updating SabreDAV namespaces
Fixed quota wrapper to return the value from flock()
hide navigation by default, not only on small screens, first step