Added .gitignore file
Replaced reference to NSURLCacheStorageNotAllowed with NSURLRequestReloadIgnoringLocalCacheData, which is of the type the method expects, and has the same intended effect. This StackOverflow answer also indicates this as a proper solution: http://stackoverflow.com/a/20739049/105717. (fixes #57)
Removed lines from .gitignore file that don't apply, since there is no Xcode project
Added code in -setObjectWithMethod... to pass along more errors in the failure handler (fixes #59)
Replacing spaces in destinationPath with pluses, since that's what S3 expects, and uploads fail without that (fixes #61)
Improved readme, bringing code example up to date, and adding a way to read the final file's URL (fxes #58)
Improved documentation for -putObject... and -postObject... regarding destinationPath, since it wasn't clear how to use it (fixes #60)
Merge branch 'issue59'
Merge branch 'issue61'
Merge branch 'issues58and60'