Bug 183733 Implement the IScriptOjectClassInfo to provide the class infromation to support the JS code assistant.
Engine should implement the IScriptObjectClassInfo interface to return the class information for script object.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/executor/ExecutionContext.java
* <li>2. classloader setted through the appContext.
	 * <li>3. CLASSPATH setted by WEBAPP_CLASSPATH_KEY
	 * <li>4. PROJECT_CLASSPATH_KEY
	 * <li>5. WORKSAPCE_CLASSPATH_KEY
	 * <li>6. JARs define in the report design
	 */
	static private class ApplicationClassLoader extends ClassLoader
	{
		private static String[] classPathes = new String[]{
				EngineConstants.WEBAPP_CLASSPATH_KEY,
				EngineConstants.PROJECT_CLASSPATH_KEY,
				EngineConstants.WORKSPACE_CLASSPATH_KEY};
		private ExecutionContext context = null;
		private ClassLoader loader = null;
		public ApplicationClassLoader( ExecutionContext context )
		{
			this.context = context;
		}
		public Class loadClass( String className )
				throws ClassNotFoundException
		{
			try
			{
				return Class.forName( className );
			}
			catch ( ClassNotFoundException ex )
			{
				if ( loader == null )
				{
					createWrappedClassLoaders( );