title: Xcode: iPhone app codesign error
body: <p>When building a new iPhone app in Xcode, I'm getting this error:</p>
  
  <blockquote>
    <p>codesign error: code signing identity
    'iphone developer' does not match any
    code-signing certificate in your
    keychain. once added to the keychain,
    touch a file or clean the project to
    continue.</p>
  </blockquote>
  
  <p>What's the fix?</p>