Adding Scatter methods

PNScatterChart in UIView

+//
+//  PNScatterChart.h
+//  PNChartDemo
+//
+//  Created by Alireza Arabi on 12/4/14.
+//  Copyright (c) 2014 kevinzhow. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+#import <QuartzCore/QuartzCore.h>
+#import "PNChartDelegate.h"
+#import "PNScatterChartData.h"
+#import "PNScatterChartDataItem.h"
+
+@interface PNScatterChart : UIView
+
+@property (nonatomic, retain) id<PNChartDelegate> delegate;
+
+/** Array of `ScatterChartData` objects, one for each line. */
+@property (nonatomic) NSArray *chartData;
+
+/** Controls whether to show the coordinate axis. Default is NO. */
+@property (nonatomic, getter = isShowCoordinateAxis) BOOL showCoordinateAxis;
+@property (nonatomic) UIColor *axisColor;
+@property (nonatomic) CGFloat axisWidth;
+
+/** String formatter for float values in y-axis labels. If not set, defaults to @"%1.f" */
+@property (nonatomic, strong) NSString *yLabelFormat;
+
+/** Default is true. */
+@property (nonatomic) BOOL showLabel;
+
+/** Default is 18-point Avenir Medium. */
+@property (nonatomic) UIFont  *descriptionTextFont;
+
+/** Default is white. */
+@property (nonatomic) UIColor *descriptionTextColor;
+
+/** Default is black, with an alpha of 0.4. */
+@property (nonatomic) UIColor *descriptionTextShadowColor;
+
+/** Default is CGSizeMake(0, 1). */
+@property (nonatomic) CGSize   descriptionTextShadowOffset;
+
+/** Default is 1.0. */
+@property (nonatomic) NSTimeInterval duration;
+
+@property (nonatomic) CGFloat AxisX_minValue;
+@property (nonatomic) CGFloat AxisX_maxValue;
+
+@property (nonatomic) CGFloat AxisY_minValue;
+@property (nonatomic) CGFloat AxisY_maxValue;
+
+- (void) setAxisXWithMinimumValue:(CGFloat)minVal andMaxValue:(CGFloat)maxVal toTicks:(int)numberOfTicks;
+- (void) setAxisYWithMinimumValue:(CGFloat)minVal andMaxValue:(CGFloat)maxVal toTicks:(int)numberOfTicks;
+- (void) setup;
+- (void) drawLineFromPoint : (CGPoint) startPoint ToPoint : (CGPoint) endPoint WithLineWith : (CGFloat) lineWidth AndWithColor : (UIColor*) color;
+
+@end