Update add plugin node-canvas , return base64 format url

[kiwilili]

The default browser, passing the {type: 'node'} parameter, will base64 format url

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[oori]

Thanks a lot for the PR, but right now I'd opt not to pull it as is. Please see my comment at https://github.com/ETCDEVTeam/hashicon/issues/23

1. Setting node-canvas as dependency will bloat this library for browser-only users, that's why I suggested we allow an alternative createCanvas function rather then type as input. This would also allow further flexibility for people with other custom canvas requirements.

2. hashicon returns a canvas, that should be consistent. so I wouldn't return base64 for node and canvas for browser. If one wants base64, they should toDataURL(), but maybe they'd want to hashicon(hash).createPNGStream() or any other output node-canvas provides.

So, I think it's better changing the renderer function to something like: function renderer(hashValues, params, createCanvasFn) (and the relevant changes for the wrapping main.js). I can do it in the next week (lack of time now).

Thanks again for your PR!

[kiwilili]

Thank you for your reply, I think your suggestion will be more suitable for the purpose of using this project.

[justinmchase]

Hey, I really need to generate these images on the server also. Any word on this?

[oori]

Closing PR. has been resolve in v0.3.0