Performance and README Updates

Updated

• Dispatch-based synchronized access to subdelegates.
  • Updated by Mattt Thompson in regards to Issue #175.
• iOS 7 instructions in the README.
  • Updated by Mattt Thompson.
• CRUD example in the README to work on Xcode 6.1.
  • Updated by John Beynon in Pull Request #187.
• The cURL example annotation in the README to pick up bash syntax highlighting.
  • Updated by Samuel E. Giddins in Pull Request #208.

Fixed

• Out-of-memory exception by replacing stringByAddingPercentEncodingWithAllowedCharacters
  with CFURLCreateStringByAddingPercentEscapes.
  • Fixed by Mattt Thompson in regards to Issue #206.
• Several issues in the README examples where an NSURL initializer needs to be unwrapped.
  • Fixed by Mattt Thompson in regards to Issue #213.
• Possible exception when force unwrapping optional header properties.
  • Fixed by Mattt Thompson.
• Optional cookie entry in cURL output.
  • Fixed by Mattt Thompson in regards to Issue #226.
• Optional textLabel property on cells in the example app.
  • Fixed by Mattt Thompson.