pull in prop-types from a separate module, fix sinon deprecation warning

[modosc]

i tested with 15.5. and 15.4 and this change worked fine - i tried to test with 0.14.x but gave up trying to chase down the required devDependencies changes. if this is important we might consider setting up multiple builds to verify older version compatibility.

[mention-bot]

@modosc, thanks for your PR! By analyzing the history of the files in this pull request, we identified @frederickfogerty, @paulstraw and @minfawang to be potential reviewers.

[frederickfogerty]

Thanks for this update @modosc. Do you know if prop-types is meant to work with 0.14.x?

If it is, then I'll release this as a patch version. If not, I'll have to release this as a breaking change.

[modosc]

well - it would certainly be easier to just support 15.5 going forward (compare to this or this - in that case i'd have to update the peerDependencies to match.

otherwise i could spend some time adding in test support for multiple react versions, etc.

[frederickfogerty]

Don't you love minor version bumps with breaking changes! /s

It's important to me that we support all 15.x versions. In saying that, I don't think we need to spend any time setting up multiple react versions, etc. Here's why:

(Can you please make sure I'm understanding this correctly)

prop-types update: This should work with all 15.x versions, so this PR is fine for that.

skin-deep/test update: This is different between React 15.5 and 15.4, but if we just run our tests on 15.5, then our tests will cover all 15.x versions of React.

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So, my current thinking is to release this as a breaking change, dropping support for React 0.14.

[modosc]

prop-types update: This should work with all 15.x versions, so this PR is fine for that.

it may not be ideal to pull in prop-types to 15.4 though since it's duplicated in React.propTypes but i tested locally with 15.4 and it did indeed work (at least, tests passed).

skin-deep/test update: This is different between React 15.5 and 15.4, but if we just run our tests

on 15.5, then our tests will cover all 15.x versions of React.
the only change for us is React.propTypes vs prop-types. skin-deep had a ton of other internal pieces in play, hence the longer pr.

[frederickfogerty]

@modosc thanks for clearing that up.

Agree it's not ideal to have propTypes duplicated, but at least it works. I'll add a note on the release notes so that people are aware of this duplication.

[modosc]

make sure to bump up the required deps in package.json to 15.5.x

[frederickfogerty]

@modosc I was thinking of bumping it to 15.x.

Also, should we list prop-types as a dependency?

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There's a bit more work I need to do on this before I can release it (e.g. remove some old deprecations), I'll get around to it this arvo.