OF-657: Update build dependencies for Java 1.5; enable caching for Crowd Group instances

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/trunk@13618 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/openfire/crowd/CrowdProperties.java

@@ -53,7 +53,7 @@ public class CrowdProperties {
 			try {
 				props.load(new FileInputStream(file));
 			} catch (IOException ioe) {
-				throw new IOException("Unable to load crowd.properties file", ioe);
+				throw new IOException("Unable to load crowd.properties file");
 			}
 		}
 		

src/java/org/jivesoftware/openfire/crowd/jaxb/Group.java

@@ -15,11 +15,13 @@
  */
 package org.jivesoftware.openfire.crowd.jaxb;
 
+import java.io.Serializable;
+
 import javax.xml.bind.annotation.XmlAttribute;
 import javax.xml.bind.annotation.XmlRootElement;
 
 @XmlRootElement(name="group")
-public class Group {
+public class Group implements Serializable {
 	@XmlAttribute
 	public String name;