systemjs/systemjs — pull request #273 by sheerun (2014-12-21 01:35:59+00:00)
Title: fix: Loader referenced to global object

When requiring in Require.js style, this
pointed to global object instead of loader.

It happened after following RequireJS shim:

```
window.require = window.requirejs = System.amdRequire;
```

This commit fixes whole class of such issues.

Basically I avoid using "this" as much as possible.