Update readme multiable line example

@@ -41,22 +41,23 @@ You will need LLVM 3.0 or later in order to build PNChart.
   PNLineChart * lineChart = [[PNLineChart alloc] initWithFrame:CGRectMake(0, 135.0, SCREEN_WIDTH, 200.0)];
   [lineChart setXLabels:@[@"SEP 1",@"SEP 2",@"SEP 3",@"SEP 4",@"SEP 5"]];
 
-  // Line Chart Nr.1
+  // Line Chart No.1
+  NSArray * data01Array = @[@60.1, @160.1, @126.4, @262.2, @186.2, @127.2, @176.2];
   PNLineChartData *data01 = [PNLineChartData new];
-  data01.color = [UIColor redColor];
+  data01.color = PNFreshGreen;
   data01.itemCount = lineChart.xLabels.count;
-  data01.getData = ^(NSUInteger item) {
-    CGFloat y = item * 10;
-    return [PNLineChartDataItem dataItemWithY:y];
+  data01.getData = ^(NSUInteger index) {
+      CGFloat yValue = [[data01Array objectAtIndex:index] floatValue];
+      return [PNLineChartDataItem dataItemWithY:yValue];
   };
-
-  // Line Chart Nr.2
+  // Line Chart No.2
+  NSArray * data02Array = @[@20.1, @180.1, @26.4, @202.2, @126.2, @167.2, @276.2];
   PNLineChartData *data02 = [PNLineChartData new];
-  data02.color = [UIColor blueColor];
+  data02.color = PNTwitterColor;
   data02.itemCount = lineChart.xLabels.count;
-  data02.getData = ^(NSUInteger item) {
-    CGFloat y = item == 0 ? (item * 5) + 10 : (item * 5);
-    return [PNLineChartDataItem dataItemWithY:y];
+  data02.getData = ^(NSUInteger index) {
+      CGFloat yValue = [[data02Array objectAtIndex:index] floatValue];
+      return [PNLineChartDataItem dataItemWithY:yValue];
   };
 
   lineChart.chartData = @[data01, data02];