fix(InternalStore): invalid value on parse

if you get an invalid value JSON.parse throws an error

localcache = {
  'yolo': undefined // should be "{swag: true, isAuthenticated: true}"
};

store.get('yolo') // JSON.parse error is thrown


localcache
moving inMemoryCache inside the try makes sense. I'm not a fan of returning twice (inside try and catch) so this works too
```javascript
      try {
        obj = saved ? JSON.parse(saved) : null;
        this.inMemoryCache[name] = obj;
      } catch(e) {
        this.remove(name);
        obj = null;
      }
      return obj;
```