Rename 'TreeEntry' RPC to 'ObjectAtPath'

create new RPC CommitService.ObjectAtPath (ObjectAtPathRequest, ObjectAtPathResponse)
fields in message are identical to TreeEntryRequest, TreeEntryResponse
server implementation uses TreeEntry back end
update clients one by one to use CommitService.ObjectAtPath instead of CommitService.TreeEntry

I think it's confusing to have an RPC CommitService.TreeEntry and a message type TreeEntry that are not related.

In #320 (comment 33482955) I get the feeling 'TreeEntry' is a domain object. But we can't use that name because we already have the RPC.

Worth renaming?

Edited Jul 06, 2017 by Andrew Newdigate

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