Add some more versioned dependencies and release 31

As this is 31 i've bumped the pho* dependencies to 0.31.0 also adding a phoc dependency to ensure it's recent (as the latest version fixes bugs in 0.30.0). I also versioned the pw dependency to make sure we don't end up with odd icons.

All this is part of the quest to have a more formal tracking of needed dependencies to get a good mobile environment out of the box.