First removal of MetaFolder

Signed-off-by: Nico Rutishauser <nr@hotmail.ch>
Delete the MetaDocument, adapt all use cases

Signed-off-by: Nico Rutishauser <nr@hotmail.ch>
Test fixing

Signed-off-by: Nico Rutishauser <nr@hotmail.ch>
Get notified if other user gets a share

Signed-off-by: Nico Rutishauser <nr@hotmail.ch>