Dynamic Image Filters and Custom Image Transitions

All issues associated with this milestone can be found using this filter.

Added

• Custom image transition to the UIImageView extension.
  • Added by Kevin Harwood in Pull Request
    #9.
• CompositeImageFilter protocol to construct composite image filters.
  • Added by Damien Rambout in Pull Request
    #8.
• DynamicImageFilter and DynamicCompositeImageFilter structs to make it easy
  to create custom image filters.
  • Added by Damien Rambout in Pull Request
    #14.

Updated

• ImageDownloader download image completion closures to be optional.
  • Updated by Christian Noon.
• Completion callback behavior of the UIImageView extension methods to be called before
  the image transition occurs.
  • Updated by Kevin Harwood in Pull Request
    #9.
• Rounded corner radius image filter can now be adjusted by the image scale.
  • Updated by Christian Noon in Pull Request
    #10.
• Enabled APPLICATION_EXTENSION_API_ONLY in watchOS framework.
  • Updated by James Barrow in Pull Request
    #11.
• The podspec file to allow all Alamofire 2.x versions.
  • Updated by Christian Noon.