added support for streams (POST/PUT), content-type header in params now case insensitive, added streaming tests and examples
bug fix: check for Readable instead of ReadStream, added PATCH method support for streaming
deleted accidentally committed file
fix: on POST/PUT/PATCH we check for Stream instead of Readable

this will allow us to use https://github.com/felixge/node-form-data to send mulitpart/form-data requests.
added example and tests for supporting multipart/form-data (browser file upload)
Update form-data dependency