[Owncloud] Showstopper Bugs for 4.5

[Arthur Schiwon]

Hey,

i tried to solve "Old links from 4.0.7 do not work in 4.5" (oc-1851) with the  
commit 
https://github.com/owncloud/core/commit/b23ad579dc674d3fdeaed0c6f650a6fcb8de6394

It relies on the Filecache, but that should be OK – and to the old table. The 
only notification to the user will be written to the ownCloud log.

Please have a look if this is OK and works for you. Comments?

@Michael: let's remove the deprecated sharing-table with OC 5.0, then.

Cheers
Arthur