Conflicting Array (and other?) module name with compiler JS code

[xash]

@lambdor found a bug with arrays when using ports: xash/Array#2

The problem is, that the compiler uses instanceof Array to check if an object is an JSArray with ports, but also var Array = Elm.Array.make(_elm); for using the module in the code, so the first one will crash. I don't know if Array is the only problematic module, or if there are more to find. However, there seem to be three solutions:
1.) Rename Array and forbid its and eventually other names for modules.
2.) Change var Module = Elm.Module.make(_elm); to something like _Module.
3.) Export an array identifier function to Utils to use it with _U.isArray(o); and fix eventually other conflicts, when they show up.

[evancz]

I think 3 can be done right now. Would you mind opening a pull request with that change?

The canonical branch makes it fairly straight forward to do solution 2, so I think that's the way to go longer term.

[evancz]

As a side note, I moved array to master to try to get 0.12.1 ready before webgl can be merged in.