Allow publishing on failure.
Update to the latest morph api

ref e3dc725134e8d65c799d1cde6aaac9664b566cd8 in
https://github.com/tildeio/htmlbars
Cleanup some un-used imports
A child view morph should not clobber existing DOM in the buffer
Update tests for ember-metal-views
Pull htmlbars in via bower.

This allows much simpler updating to new versions, just update the sha
in `bower.json`, run `bower update htmlbars` and boom: new morph
version.
Child views are only pushed into the buffer if they have no morph
Generalized htmlbars package imports
throws error when trying to insert root view that is already rendered
Remove un-used code post ember-metal-views
Update more tests for ember-metal-views

* Fix test that prior rendering of a subtree doesn’t allow rerender until it is actually inserted if the root view is or will be inserted
* Fix odd test that doesn’t really make sense anymore as it is calling a private API that is going away.
expose an instrumentation start and subscribers to get view rendering instrumentation going in a way that doesn’t cost much if there are no subscribers.
Disable some efficiency testing that will be fulfilled by Priority Queue
Remove publishing on failure.

All tests passing no need to publish on failure.
Oldest supported jQuery is 1.8.3.

We are using `jQuery.parseHTML` in
packages/ember-views/lib/system/render_buffer.js.

`parseHTML` is only available from jQuery 1.8 forward.