Bug 153896 Improve the performance of BIRT datetime-converting
The current datetime converting algorithm in birt.core, xml&flatfile ODA implementations are not efficient enough.This is because we use java's SimpleDateTimeFormatter to parse ISO8601 compatible date/time values. We should write our own datatime string parser for ISO8601 datetime format.
core/org.eclipse.birt.core/src/org/eclipse/birt/core/data/DataTypeUtil.java
for ( int i = 0; i < simpleDateFormatter.length - 1; i++ )
		{
			try
			{
				resultDate = simpleDateFormatter[i].parse( source );
				return resultDate;
			}
			catch ( ParseException e1 )
			{
			}
		}
		
		if ( source.length( ) <= 4 && source.matches( "[0-9]+" ) )
		{
			try
			{
				resultDate = simpleDateFormatter[simpleDateFormatter.length - 1].parse( source );
				return resultDate;
			}
			catch ( ParseException e1 )
			{
			}
		}
		
		if ( resultDate == null )
		{
			throw new BirtException( pluginId,
					ResourceConstants.CONVERT_FAILS,
					new Object[]{
							source.toString( ), "Date"