Fix

• fix fatal error if no access_token_url defined but needed
• do not silently do nothing if failed to create authorize url
• encode authorize url (fix scope with space)
• remove percent encoding from oauth_token

Change

• Add method removeCallbackNotificationObserver to release the observer (which wait on callback url called by website provider)
• Add "Response-Body" when request failed (@lyptt)
• oauth_verifier now public (@itchingpixels)
• Add 'state' check when receiving code #182
• Allow to send oauth parameter in URL instead of header (Withings, @jdrevet)

Other

• add to demo 500px, hatena
• document and use in demo iOS9 UIApplicationDelegate new method to handle url