Adding AppendAllNeighbors functionality

[natemiller]

Adding AppendAllNeighbors functionality

[rubak]

Actually, I plan to give the package a major overhaul this spring and summer. The current version is based on Google's old S2 source code which was released around 2009 without further official updates. In late 2017 the new official S2 version was released and we need to switch to this code base soon. Of course this doesn't help you right now, but I want to make the move before developing any new features.

[natemiller]

Thank you for the update. Definitely look forward to following the package updates

[rubak]

I have now transferred the development of the new S2 package to the r-spatial team and you should go there to watch for further development. This package will receive no further updates.