Feat/evap upload svc

* made some small improvements to evaporate provider.
* added some meat to the upload service.
* added some basic tests for upload service, other parts of upload not yet tested.
* use of uuid and env in prefixing upload file name
* additional headers for content type, disposition, and privacy
We don't need the quotes here, they'll be minified out and there's not a good reason to remove it, just wanted to make sure that you were aware.