Fix to handle when localStorage hasn't been initialized

Okay, sorry about the two pull request. Now it should be fine. The problem with the current way it works is that it requires the localStorage to already have been initialized. This should fix this. Only problem I have remaining is this error that occurs during this call `return Ember.RSVP.resolve(record);` on `line 148`:

    Assertion failed: You must use Ember.set() to access this property (of <App.User:ember327:k74ae>) ember-1.3.1.debug.js:3285
    logToConsole ember-1.3.1.debug.js:3285
    Ember.assert ember-1.3.1.debug.js:73
    Ember.MANDATORY_SETTER_FUNCTION ember-1.3.1.debug.js:3445
    (anonymous function) ember-data.js:1966
    (anonymous function) ember-data.js:4907
    (anonymous function) ember-1.3.1.debug.js:3192
    OrderedSet.forEach ember-1.3.1.debug.js:3035
    Map.forEach ember-1.3.1.debug.js:3190
    Model.reopenClass.eachTransformedAttribute ember-data.js:4906
    Ember.Object.extend.applyTransforms ember-data.js:1964
    Ember.Object.extend.normalize ember-data.js:2010
    DS.LSSerializer.DS.JSONSerializer.extend.extractSingle localstorage_adapter.js:25
    superWrapper ember-1.3.1.debug.js:1230
    Ember.Object.extend.extractSave ember-data.js:2508
    Ember.Object.extend.extractCreateRecord ember-data.js:2437
    Ember.Object.extend.extract ember-data.js:2365
    (anonymous function) ember-data.js:10318
    invokeCallback ember-1.3.1.debug.js:9427
    publish ember-1.3.1.debug.js:9097
    publishFulfillment ember-1.3.1.debug.js:9517
    DeferredActionQueues.flush ember-1.3.1.debug.js:5650
    Backburner.end ember-1.3.1.debug.js:5741
    Backburner.run ember-1.3.1.debug.js:5780
    Ember.run ember-1.3.1.debug.js:6181
    handleRegisteredAction ember-1.3.1.debug.js:36581
    handleActionEvent ember-1.3.1.debug.js:21477
    Ember.handleErrors ember-1.3.1.debug.js:899
    (anonymous function) ember-1.3.1.debug.js:21469
    x.event.dispatch jquery-2.0.2.js:4692
    y.handle