Added API to list contributors

src/test/java/org/kohsuke/github/RepositoryTest.java

@@ -1,6 +1,7 @@
 package org.kohsuke.github;
 
 import org.junit.Test;
+import org.kohsuke.github.GHRepository.Contributor;
 
 import java.io.IOException;
 
@@ -21,6 +22,24 @@ public class RepositoryTest extends AbstractGitHubApiTestBase {
         assertNull(r.getSubscription());
     }
 
+    @Test
+    public void listContributors() throws IOException {
+        GHRepository r = gitHub.getOrganization("stapler").getRepository("stapler");
+        int i=0;
+        boolean kohsuke = false;
+
+        for (Contributor c : r.listContributors()) {
+            System.out.println(c.getName());
+            assertTrue(c.getContributions()>0);
+            if (c.getLogin().equals("kohsuke"))
+                kohsuke = true;
+            if (i++ > 5)
+                break;
+        }
+
+        assertTrue(kohsuke);
+    }
+
     private GHRepository getRepository() throws IOException {
         return gitHub.getOrganization("github-api-test-org").getRepository("jenkins");
     }