Add entity removal on sync

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Add a map to the request and response with synckeys (as key of the map) and 
entity names (as value of the map).

The map on the request will be used to try to remove entities on the server. 
The map on the result are entities that have been synced before but should be 
removed on the client.

Original issue reported on code.google.com by dirkvran...@gmail.com on 11 Jan 2013 at 4:51

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Original comment by dirkvran...@gmail.com on 11 Jan 2013 at 4:52

• Changed title: Add entity removal on sync

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Original comment by dirkvran...@gmail.com on 14 Jan 2013 at 1:30

• Changed state: Fixed