Support for Node 10.x & forces ASCII for socket writes

[alecgorge]

Closes #22.

The tests still don't pass but it gives me an auth error with the test API key and when I use my own API key the test times out even though with DEBUG=* I can see everything worked fine.

[alecgorge]

The tests were originally timing out here because node-mitm doesn't stub out net.Socket.constructor.

The issue with the tests failing on v10.x are because of failures of node-mitm as well. The stubbed out socket implementation returns undefined except for v0.10.x which returns {}. Both are meant to indicate no error. In recent version of node.js (including 10.x), there is an explicit check to make sure the underlying write functions (which node-mitm stubs out) only return 0 to indicate no error through a err !== 0 check.

I don't want to submit those patches to node-mitm because:

1. I've already sunk way more time than I wanted into this to add some simple metrics to my app
2. It already should work but the test is broken

Can we have this merged and a new release cut to support 10.x and when you have time go through to make all the tests work?

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The moral of the story is that the error message is (almost) always exactly right haha:

The "err" argument must be of type number. Received type undefined

[janxious]

Probably can. One of us will look into this more tomorrow and probs cut a new release. Thanks for looking into it!

[alecgorge]

Thanks so much!

[janxious]

@alecgorge I continue to be a node novice, so do you have an opinion on the best thing to do with changes to package-lock.json in dependencies? commit whatever npm spits out?

I have a changeset that fixes the tests, and your links helped me figure out how to do it.

[alecgorge]

@janxious yup, always commit whatever npm spits it

[janxious]

Cool.

Also, there is a new version 2.3.0 out for ya.

[moll]

Just FYI I've fixed Mitm.js for Node v10. It's waiting on confirmation (tracked in moll/node-mitm#48) and should be out as patch-level release soon.