Bug 187213 Provid a writer to serialize design in document without any white space.
Add a new writer for serialize design in document without any withe space.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/util/XMLWriter.java
/**
	 * Close the write at the completion of the file.
	 */
	public void close( )
	{
		assert elementStack.size( ) == 0;
		out.close( );
		out = null;
	}
	/**
	 * Starts an XML element.
	 * 
	 * @param tagName
	 *            the name of the element
	 */
	public void startElement( String tagName )
	{
		flushPendingElements( );
		closeTag( );
		emitStartTag( tagName );
	}
	/**
	 * Implementation method to write a &ltTag start tag.
	 * 
	 * @param tagName
	 *            the tag to write
	 */
	protected void emitStartTag( String tagName )
	{
		elementStack.push( tagName );