Refactor into 4 npm packages

[Raynos]

• vtree contains the data structures & diff
• vdom contains patch & create-element that depends on vtree
• vh is an independent sugar module that depends on vtree
• vthunk is an independent widget module that depends on vtree & vdom

I also made a util-wtf folder. Please replace that with

• isarray
• is-object
• replace is-string with typeof s === 'string' which is cross browser.

Also note @Raynos is an asshole and took the name vdom-thunk on npm already.

[Raynos]

cc @neonstalwart

So myself & @Matt-Esch were talking about this refactoring.

The purpose for this refactoring is to make h optional sugar & to make vtree usable on it's own.

You can imagine that someone might write vansi or vcanvas that implements create.js and patch.js for ANSI terminal or <canvas>

[Raynos]

@Matt-Esch having audited the vtree/diff.js code the only thing that is bad is the hardcoded 'style' key.

I will generalize our 'style' handling for all objects in a seperate PR.

[neonstalwart]

i don't know that separate packages is completely necessary to achieve your goal but the separation you're suggesting seems a logical way to decompose virtual-dom so i have no objection to it.

btw, is-object isn't used anywhere.

[neonstalwart]

actually... this separation should also encourage more reuse/collaboration for things that are a different flavor of sugar (like in #22) 👍

[Raynos]

I need to update this pr to add a diff.js that is module.exports = require("./vtree/diff.js") and the same for other files so we can merge this and keep working on all 4 modules inside virtual-dom until we are ready to break them out.

That way this is a first pass at a seperation that makes sense and we can polish the seperation until we are truly happy with it.

[Matt-Esch]

The reorganization has been pushed in commit 91ad33f - expect the subdirectories to end up as standalone modules in the near future