Add functionality for pagination support in the UI
Added pageSize, total, totalPages and isFinished to AdapterPopulatedRecordArray
Added normalizeMetadata() to JSONSerializer to provide standardised access to page, pageSize, total, isFinished
Added pagination tests
metaForType() object is now an Ember.Object so it is observable
Refactored for separation of concerns in Request and AdapterPopulatedRecordArray
Changed AdapterPopulatedRecordArray.page to startPage and endPage