Removes usage of deprecated Error objects.
Updating field reference in page.
Commenting-out unused future methods to increase code coverage.
Using new Error_Settings__c custom setting.
Forgot to commit the changes to the Error__c object.
Merge pull request #230 from SalesforceFoundation/feature/189-use-new-error-object

Feature/189 use new error object
Merge dev into feature/172-all-opp-triggers-to-TDTM