Rip out local archive/move/delete for folders.

In the post folder/label split world, it makes no sense to have local
folder actions, since Inbox doesn't care much about folders, only Inbox
labels. If we want to support these for backcompat, we may need to have
pluggable modules like the actions remote syncback, because different
providers have different semantics. For example, Gmail has no 'archive'
folder so it needs to do something different than a remote provider that
does for 'archiving' mail.