Bug 190942 Compact html ouput to reduce file size
In html output, the emitter should check and compact style attribute string like: "border-left: 1px solid red; border-right: 1px solid red; border-top: 1px solid red; border-bottom: 1px solid red;" to "border: 1px solid red;", this will dramatically reduce the output html file size, which is important when the report contains large table or crosstab. This is also true for padding, margin and other style properties.
engine/org.eclipse.birt.report.engine.emitter.html/src/org/eclipse/birt/report/engine/emitter/html/HTMLEmitter.java
* Build size style string say, "width: 10.0mm;".
	 * 
	 * @param content
	 *            The <code>StringBuffer</code> to which the result is output.
	 * @param name
	 *            The property name
	 * @param value
	 *            The values of the property
	 */
	public void buildSize( StringBuffer content, String name,
			DimensionType value )
	{
		if ( value != null )
		{
			content.append( ' ' );
			content.append( name );
			content.append( ": " );
			content.append( value.toString( ) );
			content.append( ';' );
		}
	}
	/**
	 * adds the default table styles
	 * 
	 * @param styleBuffer
	 */
	protected void addDefaultTableStyles( StringBuffer styleBuffer )
	{
		styleBuffer.append( "border-collapse: collapse; empty-cells: show;" ); 
	}