owncloud: Reworked read and write to operate on local copies.
owncloud: Reworked read and write to operate on local copies.

This creates local temporary files and uses them to transfer the data
(GET and PUT requests).

gco/csync,gco/csync,meeh420/csync,meeh420/csync,gco/csync,meeh420/csync,gco/csync