Support Circular Dependencies

Nobody has claimed this yet.

Our babel plugin for variable recordering is currently not capable of handling circular imports properly.

Circular dependencies are solved in SystemJS via their module rewriting.
To be specific, SystemJS uses local variables to represent import bindings.
These variables are set as specified in the `setters` functions.
```JavaScript
var html, pt;
return {
setters: [function (_htmlJs) {
html = _htmlJs.default;
}, function (_graphicsJs) {
pt = _graphicsJs.pt;
}],
execute: function () {
_recorder_._05580698383529998.html = html;
_recorder_._05580698383529998.pt = pt;

class ContextMenu {
[...]
```
`setters` are generated once for each import.

If we now have a circular dependency, that variable is initially set to `undefined`.
Then, the module's `execute` function runs, producing some exports.
These exports are then used to load the circular dependent module properly.
Afterwards the exports of the circular dependent module are set again with the `setters` functions.
However, the module's `execute` does not run again.
Thus, our variable recorder field are not assigned again.
They are only assigned in the module's first run with all values of imports being `undefined`.

---

We have to rewrite the module-scoped variables in a different way.

Start by locating the Babel plugin for variable reordering and compare its handling with the SystemJS module rewriting and setters described here. Done means circular imports no longer leave variable recorder fields assigned only from their initial undefined values, and the dependent module receives the later export values.

Written by the indexing model from the issue text.