Bug 152443 Support boolean type in data set
Support boolean type in data set. It'll cause some data transform issue with absence of boolean type.
core/org.eclipse.birt.core/src/org/eclipse/birt/core/data/DataTypeUtil.java
return resultDate;
		}
		catch ( ParseException e1 )
		{
			throw new CoreException( 
					ResourceConstants.CONVERT_FAILS,
					new Object[]{
							source.toString( ), "Date"
					} );
		}
	}
	/**
	 * Call org.eclipse.birt.core.format.DateFormatter
	 * 
	 * @param source
	 * @return
	 */
	private static String toString( Date source, ULocale locale )
	{
		DateFormatter df = null;
		
		df = (DateFormatter) ( dfMap.get( locale ) );
		if ( df == null )
		{
			synchronized ( dfMap )
			{
				df = (DateFormatter) ( dfMap.get( locale ) );
				if ( df == null )
				{
					df = new DateFormatter( locale );