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
return source;
		if ( toTypeClass == Integer.class )
			return toInteger( source );
		if ( toTypeClass == BigDecimal.class )
			return toBigDecimal( source );
		if ( toTypeClass == Boolean.class )
			return toBoolean( source );
        if ( toTypeClass == Time.class )
            return toTime( source );
		if ( Date.class.isAssignableFrom( toTypeClass ) ) 
			return toDate( source );
		if ( toTypeClass == Double.class )
			return toDouble( source );
		if ( toTypeClass == String.class )
			return toString( source );
		if ( toTypeClass == Blob.class )
			return toBlob( source );
		throw new BirtException( pluginId,
				ResourceConstants.INVALID_TYPE,
				resourceBundle );
	}
	/**
	 * Boolean -> Integer
	 * 		true 	-> 1
	 * 		others 	-> 0 
	 * Date -> Integer
	 * 		Date.getTime();
	 * String -> Integer
	 * 		Integer.valueOf();
	 * @param source