Overhaul of Validator/Parser approach, updating related files to accomodate

 * Backpedaled on prior approach. Breaking change ftw.
 ** made all public methods operate on the row
 ** all field level methods are protected or greater restriction
 ** all logic-containing methods control their own error generation
 ** Added extensive notes to Parser/Validator to reflect expected use/approach
 * Changed Parser/Validator abstracts to have 'Row' in filename to reflect semantic use
 * Renamed AbstractReaderResponse to ReaderResponse.
 * Removed Parser/Validator response, moved all functionality into generic ReaderResponse object
 ** Added rowData, getters & setters to ReaderResponse
 * Created ResponseHandler class for classes expecting to deliver a reader response. Should (theoretically) be usable either as a property, or by extending the class
 * Updated CsvFileReader to handle new validator/parser approach