Added a --tor switch to cipfs get. Requires cURL

[geebotron]

Means that the "get" feature of the CIPFS script doesn't require a local IPFS instance running. I think this is important - as you can then share the CIPFS script and generated tokens with those who don't themselves run a local IPFS instance.

Allows "get" downloads from a web entry point to IPFS, anonymously, via tor.

Requires local tor service, and availability of cURL.