MODE-2323 Removed the proxy layer and delta write functionality in Schematic

ModeShape's is no longer using Infinispan in ways where these pieces of functionality are useful.
Removing them should simplify the logic to represent more of what we're actually doing. See MODE-2323 for details.
since the current code from WSC uses conditional logic: 
`if (!documentStore.prepareDocumentsForUpdate(keysToLock))`, I'd say yes, we should keep the flag. Otherwise, according to the ISPN Javadoc (which again, I cannot vouch for) we would get exceptions in case of a timeout as opposed to a boolean result.