Rename "shell" to "node" for ease of use?

[jbenet]

I really like the "shell" name. But the IPFS api uses the naming "Node". to comply with that we should either switch or expose a "Node" type or functions or even a package that translates the wording.

[ghost]

Shell will be deprecated in favor of an impl of the CoreAPI interfaces currently living in go-ipfs/core/coreapi/interface (to be extracted into their own package).

[bonedaddy]

I think shell is a nice name. It sounds like you're establishing a shell to interact with the underlying IPFS node 😄