chore(deps): es6-shim from NPM

No need to use fixed version from github anymore.
style: normalize empty lines, Inject on class

Conflicts:
	test/injector.spec.js
style: normalize empty lines, Inject on class
fix: instantiate default providers in correct injector

When using default provider (instantiating the token), we should follow the same policy as with regular (defined/overridden) providers - that is, instantiate in the oldest injector where defined/overridden, respecting forced new instances by scope annotations.

Thus each injector has to remember what scopes it forces new instance for so that when a default provider is being instantiated later it knows whether it should be instantiated in the current injector or in a parent one.

Fixes #36