Extract CsvReader - remove built in date, time, dateTime parsing - use StringParser instead

Just always use our own StringParser lambda function instead for parsing date, time and dateTime types.

ebean-api/src/main/java/io/ebean/text/StringParser.java

@@ -5,6 +5,7 @@ package io.ebean.text;
  * <p>
  * Basic interface to support CSV, JSON and XML processing.
  */
+@FunctionalInterface
 public interface StringParser {
 
   /**