title: Swift 2.0, Xcode 7 issue
body: <p>I was using RAMAnimatedTabBarController Module from here:
  <a href="https://github.com/Ramotion/animated-tab-bar" rel="nofollow">https://github.com/Ramotion/animated-tab-bar</a></p>
  
  <p>I developed my entire application in swift 1.2 using Xcode 6 and the app was running perfectly . I wanted to try out "side loading" of my app using Xcode 7 which has swift 2.0. I had too many errors and I managed to solve most of the errors but three.</p>
  
  <p>1) This line of code which is from that RAMAnimatedTabBarController module is throwing an error saying the function can't be evoked, when this perfectly compiled in Xcode 6:</p>
  
  <pre><code> var  constranints = NSLayoutConstraint.constraintsWithVisualFormat(formatString,options:NSLayoutFormatOptions.DirectionRightToLeft,metrics: nil,views: containersDict as [NSObject : AnyObject])
  </code></pre>
  
  <p>the compiler error for this was:</p>
  
  <blockquote>
    <p>Cannot invoke 'constraintsWithVisualFormat' with an argument list of
    type '(String, options: NSLayoutFormatOptions, metrics: nil, views:
    [NSObject : AnyObject])'</p>
  </blockquote>
  
  <p>2) Another unusual error was thrown:</p>
  
  <blockquote>
    <p>linker command failed with exit code 1 (use -v to see invocation)</p>
  </blockquote>
  
  <p>3) And another:</p>
  
  <blockquote>
    <p>(null): error: cannot parse the debug map for
    "/Users/Rakshith/Library/Developer/Xcode/DerivedData/Blubot-heabwwmhqxxvctaabxkwcpgzsadx/Build/Intermediates/SwiftMigration/Blubot/Products/Debug-iphonesimulator/BlubotTests.xctest/BlubotTests":
    No such file or directory</p>
  </blockquote>
  
  <p>What is actually wrong with my project? It is still set to iOS 8.3.</p>