Add next page navigation for RDAP entity searches

A couple methods were moved to new locations so they are accessible to all types of search queries, not just nameservers like they originally were.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=179089014

java/google/registry/model/contact/ContactResource.java

@@ -121,6 +121,10 @@ public class ContactResource extends EppResource implements
     return internationalizedPostalInfo;
   }
 
+  public String getSearchName() {
+    return searchName;
+  }
+
   public ContactPhoneNumber getVoiceNumber() {
     return voice;
   }