Merge the JS module from WebSharper.Main with the JS type from WebSharper.JavaScript

[Tarmil]

The former is entirely comprised of inlines, I think its place should be in the WIG definition. This would also make it more consistent to use from C#, instead of separate JS and JSModule.

The only non-trivial part of this would be moving AnimationFrameResource, which is not a simple BaseResource and therefore can't be defined in WIG. I guess it would have to be defined in WS.Core.

[Jand42]

Moved this to 4.3 column, we should not introduce binary breaking changes in patch releases.

[Tarmil]

A difficulty with this: WIG is unable to define a generic F# value JS.Undefined : 'T.

[Tarmil]

The part of JS that is currently defined in the WebSharper.JavaScript assembly is just functions that are, in js, defined on the window object, plus Inline which is a WebSharper construct. So what we should do is:

1. Ensure that these functions are defined on the Window proxy.
2. Define aliases for them in the module WebSharper.JavaScript.JS in the WebSharper.Main assembly.
3. Remove the class WebSharper.JavaScript.JS from the WebSharper.JavaScript assembly.