Install default error handler on ApplicationRoute#actions, not #events

Fixes an issue where `error` events would still
be handled by the default error handler installed
on ApplicationRoute#events, causing deprecation
warnings.
TESTING_DEPRECATIONS refactor in various testcases

teardown ftw
Use the declared variable
Merge pull request #3313 from marcioj/use-the-declared-variable

Use the declared variable
Fix route name in code comment
Merge pull request #3314 from balinterdi/fix-route-name-in-comment

Fix route name in code comment
As the container api is currently for internal use, and YUI doesn't
seem to allow marking an entire class or module as private. Simply hide
it for now. This will hopefully prevent some confusion, but power-users
can still read the documention.
Merge pull request #3317 from stefanpenner/hide-container-api-for-now

As the container api is currently for internal use, and YUI doesn't
Fix Em.Computed.not example typo error
Merge pull request #3320 from selva-G/fix_computed_not_typo

Fixes Em.Computed.not example typo error
add inline doc for deprecated Ember.State/StateManager

to close #3316
Merge pull request #3321 from bradoyler/patch-1

add inline doc for deprecated Ember.State/StateManager
Add defeatureify to Travis config.
Incorrect error message in router.js
Merge pull request #3325 from rutinerad/patch-1

Incorrect error message in router.js
Improve message and logic around UnrecognizedURLError
Merge pull request #3326 from trek/improve-message-and-logic-for-unrecognzied-urls

Improve message and logic around UnrecognizedURLError
Only throw an initialValue error if it is null or undefined (i.e. not 0 or some other falsy value)
Merge pull request #3327 from matthooks/master

Allow reduceComputed to have an initial value of 0.
Add shortcut for whitelisting all modifier keys on {{action}}
Modifier key-independent action helper use cases can be less verbose and more future-proof.