1.0.48.9: better source information for compile-time type errors

1.0.48.9: better source information for compile-time type errors

  Compile-time warning: in addition to the context, also tell exactly
  which form produces the value that is not of the expected type.

  Run-time error: include both the error context and exact form in the
  error message.

  Delete VALUES-TYPE-ERROR, and use SIMPLE-TYPE-ERROR for both legs in
  %COMPILE-TIME-TYPE-ERROR.