added test item json file for creating a custom item request
added deserialization to object from json dictionary for pioitem and piouser. Also added extra properties to support the full PIO API
fixed small mutability bug init method
updated client and corresponding tests for using PIO objects in api response
updated build settings for the iOS 7.1 sdk
fixed deserializing in PIOItem.m  and fixed getRequestParams method in PIOCreateItemRequest.m
Merge pull request #2 from agrinman/master

Returning PIO objects in SDK methods, New tests methods