Add core data framework.
Update CREAIPointAnntation class.
Update CREAIPointAnnotation class.
Save data with core data when add a pin or drag a pin.
Change the class name from CREAIPointAnnotation to CREPointAnnotation.
Create CREAddress class that is a relevant class of the address property separated from CREPointAnnotation.
Add a method for set up managed object.
Update the method for set up managed object.
Use the constant not a string.
Load all pins form core data and view on map view when view will appear.