[BUGFIX beta] Consistently use isStream helper.
Merge pull request #9913 from rwjblue/use-is-stream

[BUGFIX beta] Consistently use isStream helper.
[BUGFIX beta] Allow AST plugins to be registered.
Merge pull request #9925 from rwjblue/htmlbars-split-plugins

[BUGFIX beta] Allow AST plugins to be registered.
[DOC] Remove extra word from beforeModel
Merge pull request #9933 from kimroen/patch-2

[DOC] Remove extra word from beforeModel
[DOC beta] Update README.md for language fix

Update README.md to improve language parallelism in steps in "How to Run Unit Tests"

BEFORE: "Then visit http://localhost:4200/. This will run all tests."
AFTER: "To run all tests, visit http://localhost:4200/."
Merge pull request #9934 from alextsg/patch-1

[DOC beta] Update README.md for language
Removes obsolete files

Seems like it's not needed anymore. If that's not the case, feel free to
close this PR.
Merge pull request #9898 from twokul/obsolete-file

Removes obsolete file
[BUGFIX beta] expose Ember.Backburner

exposes Backburner on Ember for private use by
Ember Data.
Merge pull request #9937 from fivetanley/feature-ember-metal-expose-backburner

[bugfix beta] expose Backburner as Ember.Backburner
[BUGFIX beta] Use a shared util for classNameBindings
Run Ember in node

This commit removes any strict dependencies on browser-only APIs.
Anything user agent specific (such as window, document, etc.) are
abstracted out into a new `environment` object.

Currently we feature detect whether a DOM implementation is available
and only enable certain behavior if so. The intent of the feature
detection is to determine if a DOM implementation is available, not
whether we’re running in the browser or in node. This makes it possible
to run Ember in a node environment with a “fake” DOM.

This commit also introduces some refactoring to the location APIs, such
that hardcoded document/history/navigator dependencies are reduced.

Note that some APIs are guarded with `environment.hasDOM` checks.
Code inside those guards can freely use DOM APIs, but some of those
APIs are needed for full server-side usage of Ember. This is a first
step that is designed to explicitly separate out code with DOM
dependencies from isomorphic code. Further PRs will implement the
Renderer and Location APIs for non-DOM environments.
Merge pull request #9931 from mixonic/class-name-bindings

[BUGFIX beta] Use a shared util for classNameBindings
[BUGFIX beta] Failing tests for instrument without payload
[BUGFIX beta] Support instrument without payload
Merge pull request #9947 from raycohen/intrument-without-payload

when no payload is passed to instrument, manage args properly
clean up createChildView

This makes the code more clear and prevents
overwriting arguments which likely causes
de-opts (though these fns probably still
de-opt for other reasons).
Add tests for node compatibility