UIImage Additions (With cache and request management included) ###Features:

• Load image from Internet with NSURLConnection.
• Cache image locally into disk, BUT NO Cache policy support so far,(No expiration mechanism, once cached never refreshed).
• Efficient image decoding based on extra gcd queue to predecode.

###Usage:

first, set a loader for all UIImageView

_imageLoader = [[JOImageLoader alloc] init];
[UIImageView setImageLoader: _imageLoader];

then:

UIImageView * v = nil;
[v setImageWithUrlString: @"http://www.test.com/test.jpg"];

or,

[v setImageWithUrlString: urlstring placeHolder:nil animate:NO indicator:NO]

###Todo:

• Add support for cache control.(etag, Expires, if-not-modified,etc)

###Notes for me:

• only save origin image into disk even if called with downscalation.