Added credits in the right places.

Doc/tut/tut.tex

@@ -4087,6 +4087,7 @@ be useful.
 
 \chapter{Floating Point Arithmetic:  Issues and Limitations
          \label{fp-issues}}
+\sectionauthor{Tim Peters}{tim_one@msn.com}
 
 Floating-point numbers are represented in computer hardware as
 base 2 (binary) fractions.  For example, the decimal fraction
@@ -4252,6 +4253,7 @@ supply flexible and easy ways to round float results for display.
 
 \section{Representation Error
          \label{fp-error}}
+\sectionauthor{Guido van Rossum}{guido@python.org}
 
 This section explains the ``0.1'' example in detail, and shows how
 you can perform an exact analysis of cases like this yourself.  Basic