Enqueuing Multiple Image Downloads, Cached Image Transitions and Bug Fixes

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Added

• Ability for ImageDownloader to enqueue multiple image downloads at once.
  • Added by Jeff Kelley in Pull Request
    #51.
• Tests to verify image view can cancel and restart the same request.
  • Added by Christian Noon in Regards to Issue
    #55.
• Precondition to ImageCache ensuring memory capacity is GTE preferred usage after purge.
  • Added by Christian Noon in Regards to Issue
    #56.
• Ability for image transitions to run when image is cached if specified.
  • Added by Jarrod Robins in Pull Request
    #50.
• Test to verify Accept header is set correctly on UIImageView extension.
  • Added by Christian Noon in Regards to Issue
    #60.
• Added ReleaseTest configuration to allow running tests against optimized build.
  • Added by Christian Noon.

Updated

• Project to disable testability on release and to only build tests on when testing.
  • Updated by Christian Noon.
• The Travis-CI configuration to Xcode 7.2, iOS 9.2, tvOS 9.1 and watchOS 2.1.
  • Updated by Christian Noon.

Fixed

• Issue where image was not downloaded when cancelled and restarted.
  • Fixed by Christian Noon in Regards to Issue
    #55.
• Issue where af_setImageWithURL was not using acceptable content types.
  • Fixed by Branden Russell in Pull Request
    #61.