EmberDebug should start before the application initializes

Several tabs (Promise, Render Speed) need to start logging the moment the application is initialized.
Instead of waiting for domready, we start EmberDebug immediately when the application initializes.

Things that require domready such as setting up connections are moved
to the adapter.
Merge pull request #280 from emberjs/init-ember-debug

EmberDebug should start before the application initializes