Allow the generator to use templates from GitHub #130

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Feature request

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What problem does this feature solve?

Create a Saber app using custom template

What does the proposed API look like?

npm init site my-site --template user/my-saber-starter

We should also add a saber create command which maps to npm init site or yarn create site

How should this be implemented in your opinion?

N/A

Are you willing to work on this yourself?

Yes.