Need command `goby init`

[nskins]

We need to replace the current call goby (which scaffolds out a small project into a directory goby-project/) with a call goby init that does the same but using the working directory as the root of the new Goby project.

This better models the way I've seen most projects handle initializing a new project.

[erayalkis]

I'd like to try and handle this if that's alright!