tdf#75256 Sifr icons for the startcenter part 3

Jay Philips suggested me to round up the folder icon.
And a new remote-documents icon (with a cloud).

Change-Id: I3852fd012aea92812daaad69dff11d862841b046
Reviewed-on: https://gerrit.libreoffice.org/19175Reviewed-by: Yousuf Philips <philipz85@hotmail.com>
Tested-by: Yousuf Philips <philipz85@hotmail.com>