face: Renaming (remove)registerPrefix to (unset)interestFilter

Change-Id: I1a9d4905f53c3352d916f5762c5471491f004cd2
diff --git a/include/ndn-cpp/face.hpp b/include/ndn-cpp/face.hpp
index fe49904..3204ae0 100644
--- a/include/ndn-cpp/face.hpp
+++ b/include/ndn-cpp/face.hpp
@@ -118,7 +118,7 @@
    * @return The registered prefix ID which can be used with removeRegisteredPrefix.
    */
   uint64_t 
-  registerPrefix
+  setInterestFilter
     (const Name& prefix, const OnInterest& onInterest, const OnRegisterFailed& onRegisterFailed, const ForwardingFlags& flags = ForwardingFlags(), 
      WireFormat& wireFormat = *WireFormat::getDefaultWireFormat())
   {
@@ -132,7 +132,7 @@
    * @param registeredPrefixId The ID returned from registerPrefix.
    */
   void
-  removeRegisteredPrefix(uint64_t registeredPrefixId)
+  unsetInterestFilter(uint64_t registeredPrefixId)
   {
     node_.removeRegisteredPrefix(registeredPrefixId);
   }