Move off of using System._loader.loads, in favor of System.normalizeSync

[internettrans]

See https://github.com/systemjs/systemjs/issues/1277 for why. Will first have to wait for https://github.com/CanopyTax/sofe/issues/30 to be resolved.

[internettrans]

Or even better, just use context.id, where context is the second parameter passed to the callback given to System.register. That is the same as the normalized module name. See the further discussion in the systemjs issue linked to above for more info.