Minor code reorganization
Minor code reorganization

* Add comment regarding root view controller load order
* Remove vestigial setupRootViewController method

xNUTs/MIT-Mobile-for-iOS,MIT-Mobile/MIT-Mobile-for-iOS,MIT-Mobile/MIT-Mobile-for-iOS,smartcop/MIT-Mobile-for-iOS,xNUTs/MIT-Mobile-for-iOS,smartcop/MIT-Mobile-for-iOS