Converts a key to the format of a String to the desired case. The state of the Case accessible via CaseAccessor.getCase() has not an effect on some of the methods. For example it has no effect on toCamelCase(), but it has an effect in toSnakeCase(String).
Sets the rows Case to use returns this builder as of the Builder-Pattern.
aKey - The key to be converted.
aCase - The Case to be used when printing a row or the header.
This CaseAccessor.CaseBuilder instance to continue configuration.