ValueConverter: Avoid excessive quotation marks
ValueConverter: Avoid excessive quotation marks

- Whenever a class failed to construct, we wrapped the message in
  `"-msg-".` which lead to `"Some error.".` ... which is kinda overkill
  on the quotation marks and periods. ;-)

SteveJobzniak/LazyJsonMapper,aitte2/LazyJsonMapper,aitte2/LazyJsonMapper,SteveJobzniak/LazyJsonMapper