Be able to select all pages when adding to collection (Bug 1349311)

The 'Add pages to collection' list needs an all/none option.

Change-Id: I36e3ae4c5066e0963cb9da8f1b5a824c61de7d68
Signed-off-by: Robert Lyon <robertl@catalyst.net.nz>
Merge "Be able to select all pages when adding to collection (Bug 1349311)"