1. Clean up code

2. Refactoring work
3. Optimization work. SMACK-153
4. Fixed roster test cases. SMACK-154
4. Fixed vCard issue. SMACK-152

git-svn-id: http://svn.igniterealtime.org/svn/repos/smack/trunk@4538 b35dd754-fafc-0310-a699-88a17e54d16e

source/org/jivesoftware/smack/util/Cache.java

@@ -549,7 +549,7 @@ public class Cache implements Map {
          */
         public String toString() {
             LinkedListNode node = head.next;
-            StringBuffer buf = new StringBuffer();
+            StringBuilder buf = new StringBuilder();
             while (node != head) {
                 buf.append(node.toString()).append(", ");
                 node = node.next;