node-pre-gyp brings in over 100 new dependencies.

## Issue or Feature

I know this was mentioned partially in #1108, but I feel this should be brought up directly into it's own issue.

Before node-pre-gyp, canvas was a very tiny lib, requiring a mere _single_ dependency. This was actually a large draw to the project for me. Now however, as you can see by [this lovely visualization](http://npm.anvaka.com/#/view/2d/node-pre-gyp), it is _over 100_. That's a _massive_ increase in the amount of packages we need to bring in to use canvas all for a prebuild that may not even function as expected or be wanted by the developer. I would be fine with this if it were a small package providing the same functionality, but over 100 deps for a prebuild that only ever runs a single time is a little ridiculous. I'm aware replacing request would fix a lot (mapbox/node-pre-gyp#340), but this would still be a huge dependency even without it, and I'm confused as to why this is necessary at all. Please reconsider bringing such a huge dependency into the project, it's really not good for anyone to be subjected to such dependency hell.

## Your Environment
* Version of node-canvas (e.g. 1.4.0): 2.0.0-alpha.11
* Environment (e.g. node 4.2.0 on Mac OS X 10.8): node 9.8.0 (though it applies to all OSes)