Added code to purge entries who references have been collected. Test contributed by Brian Stansberry.

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/logging/trunk@139058 13f79535-47bb-0310-9956-ffa450edef68

optional/src/test/org/apache/commons/logging/impl/WeakHashtableTest.java

@@ -232,5 +232,8 @@ public class WeakHashtableTest extends TestCase {
                 bytz = bytz * 2;
             }
         }
+        
+        // Test that the released objects are not taking space in the table
+        assertEquals("underlying table not emptied", 0, weakHashtable.size());
     }
 }