SEC-2326: CsrfRequestDataValueProcessor implements RequestDataValueProcessor

Previously there was unecessary complexity in CsrfRequestDataValueProcessor
due to the non-passive changes in RequestDataValueProcessor. Now it simply
implements the interface with the methods for both versions of the interface.
This works since linking happens at runtime.
SEC-2434: Update to Spring 3.2.6 and Spring 4.0 GA