Implemented methods in class LocalMenuDataProvider:
	+ (void) loadMenuDataWithBlock: (void (^)(MenuModel*, NSError*))callback;
	+ (MenuModel*) menuModelWithEntityCategories: (NSString*)entityCategories andEntityItems: (NSString*)entityItems;
	+ (NSMutableArray*) getCategoriesFromManagedCategories: (NSArray*)managedCategories;
	+ (NSMutableArray*) getItemsFromManagedItems: (NSArray*)managedItems;
	+ (void) addElementsFromCategories: (NSArray*)categories items: (NSArray*)items toMenuModel: (MenuModel*)menuModel ;
	+ (NSMutableArray*) findInCategories: (NSArray*)categories byParentId: (NSUInteger)parentId;
	+ (NSMutableArray*) findInItems: (NSArray*)items byCategoryId: (NSUInteger)categoryId;
These methods needs us for creation menu model from data in local data base.