remove unnecessary uses of `call` / `apply`
Merge pull request #3835 from stefanpenner/master

remove unnecessary uses of `call` / `apply`
use @wycats amd micro-loader, which supports relative paths
restore sync assertions. This will hopefully help in failure
scenarios, and prevent aging.

Now that we ship with a default RSVP.on('error', ... ) that raises
awareness, promise swallowed assertions should be no more.
Merge pull request #3831 from stefanpenner/restore-sync-assertions

Restore sync assertions