Bug #994: Updates to allow address update code to work with State & Country picklists enabled

Modify triggers related to the updating the Account and Contact objects for address changes to first validate the value against the set of valid State and Country picklist codes/values, if that feature is enabled in the Org. Potential errors due to a state or country value that cannot be matched against the configured codes/labels is logged as to the Error__c object; and the change is not made to the record.