Fixed order of applying changes when forwarding transactions

Commit 5659f588f80522a5be5c80d0e5ff34068b5f4786 changed the semantics of
remove/update operations such that the order of application became
significant: remove, then put.

Unfortunately we failed to notice that there are two places which apply
the operations in wrong order, thus breaking clients who perform a
remove/put in a single transaction -- e.g. replacing data without
merging it.

Fix DataStore and Binding->DOM connector.

Change-Id: I4fb12730e8256d3614846adb1fa5a1096284e0eb
Signed-off-by: Robert Varga <rovarga@cisco.com>
Signed-off-by: Tony Tkacik <ttkacik@cisco.com>