BREAKING CHANGE
Previously a content binding of a component was visible to the directives in its view with the host constraint. This is not the case any more. To access that binding, remove the constraint.
BREAKING CHANGE:
This change moves the http module into angular2/, so its import
path is now angular2/http instead of http/http.
Many other modules have also been moved around inside of angular2,
but the public API paths have not changed as of this commit.