Automatic merge from submit-queue

fix edit on list

Fixes https://github.com/kubernetes/kubernetes/issues/20519

This reverts the implementation that removed list editing capability, but leaves its tests intact.  This allows edits of lists to work, while still allowing mutation of the annotations.  It does this by walking each item and building per item patches.

The current implementation will do funny things if you delete entire list entries.  A followup could be written to locate the correct list item by name.  Right now, it just rejects the patch because its trying to change an immutable field.

@janetkuo @kubernetes/kubectl @kargakis