sets token argument to nil

and generatings uuid in initialize
improves Processor class in a number of ways

- removes thumbnail_size attr_reader (let Configuration be the source of
  truth for that value)
- improves variable naming, and makes it consistent
- adds `stream` method for writing the image out to a StringIO stream
- adds `original` method to provide noop processing of the image
- updates and expands specs to keep up with changes
improves Transmitter flow and interface

- `transmit!` method now returns true/false from `Service.response.successful?`
- moves `connect!` to initialization
- once `transmit!` has been called, the new `url` method returns the url
  for the file just uploaded
- updates specs to keep up with changes

This class is in flux and may still change.
fleshes out the Uploader and improves interfaces

- moves content_type, and original_filename to attr_reader
- removes unused original_file method
- adds `Uploader.version` macro for registering file versions
- adds `Uploader.versions` for returning a hash of the registered versions
- adds `versions` instance method for reading `Uploader.versions`
- adds `processor` and `namer` methods that return memoized instances of
  `Processor` and `Namer`, respectivley
- adds `upload!` method to loop over `versions` and upload the processed
  files to s3, collecting the urls into `@uploads`
- adds `uploads` attr_reader
removes Rack::Test::Methods inclusion
updates readme with extended usage information and customization options
Bump to 0.0.2