Bug 134662 An unfriendly message pop up when input a very large number in filter Top N
Description: May be Top N value should be less than 100000 but the error message to user is not friendly enough. Step to reproduce: 1.new a datasource and a dataset 2.in the dataset add a filter with top N 3.enter 3655566 in top n 4.click the "Preview Results" Actual result: An error message tell that "data.engine.InvalidTopBottomN100000" Expected result: It had better tell user the Top N's rage of the input
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/NEvaluator.java
private FilterPassController filterPassController;
	protected static final String nullValueReplacer = "{NULL_VALUE_!@#$%^&}";
	/**
	 * Create a new instance to evaluate the top/bottom expression
	 * @param operator 
	 * @param op_expr operand expression
	 * @param n_expr expression to yield N 
	 * @return
	 */
	public static NEvaluator newInstance( int operator, IScriptExpression op_expr, 
			IScriptExpression n_expr, FilterPassController filterPassController, IExecutorHelper helper  )
	 	throws DataException
	{
		NEvaluator instance = null;
		switch ( operator )
		{
			case IConditionalExpression.OP_TOP_N :
				instance = new TopNEvaluator();
				instance.n_percent = false;
				break;
			case IConditionalExpression.OP_TOP_PERCENT:
				instance = new TopNEvaluator( );
				instance.n_percent = true;
				break;
			case IConditionalExpression.OP_BOTTOM_N:
				instance = new BottomNEvaluator( );
				instance.n_percent = false;
				break;
			case IConditionalExpression.OP_BOTTOM_PERCENT:
				instance = new BottomNEvaluator( );