Support for ASIHTTPRequest

Experimental support for ASIHTTPRequest

At this moment Nocilla supports stubbing request made with ASIHTTPRequest. This feature is experimental for the moment and more testing in the wild needs to be done. It has been tested with the classes ASIHTTPRequest and ASIFormDataRequest. It has not been tested for ASIWebPageRequest, ASICloudFilesRequest or ASIS3Request.
If you want to enable it, point to the podspec in this repo and register the hook before starting Nocilla, like this:

pod 'Nocilla', :podspec => 'https://raw.github.com/luisobo/Nocilla/master/Nocilla.podspec'

[[LSNocilla sharedInstance] registerHook:[[LSASIHTTPRequestHook alloc] init]];
[[LSNocilla sharedInstance] start];