Download, cache, render small images with UIImageView category

#import "FlyImage.h"
...

UIImageView *imageView = [[UIImageView alloc] initWithFrame:frame];
[imageView setPlaceHolderImageName:@"default"
						thumbnailURL:[NSURL urlWithString:@"http://thumbnail"]
						originalURL:[NSURL urlWithString:@"http://original"]];
[]self.view addSubview:imageView];
...

UIImageView *iconView = [[UIImageView alloc] initWithFrame:frame];
[iconView setIconURL:[NSURL urlWithString:@"http://original"]];
[]self.view addSubview:iconView];
...

// retrieve a specific key, and get callback
[[FlyImageCache sharedInstance] asyncGetImageWithKey:key
	  									   completed:^(NSString *key, UIImage *image) {
		imageView.image = image;
}];

// remove a image from the cache	
[[FlyImageCache sharedInstance] removeImageWithKey:key];

// delete all images
[[FlyImageCache sharedInstance] purge];

// add a new icon with a specific key
[[FlyImageIconCache sharedInstance] addImageWithKey:key
        size:drawSize
        drawingBlock:^(CGContextRef context, CGRect contextBounds) {
        	UIImage *image = [UIImage imageWithName:@"imageName"];

    		UIGraphicsPushContext(context);
		    [image drawInRect:contextBounds];
		    UIGraphicsPopContext();
        }
        completed:nil];

// retrieve a specific key, and get callback
[[FlyImageCache sharedInstance] asyncGetImageWithKey:key
	  									   completed:^(NSString *key, UIImage *image) {
		imageView.image = image;
}];