comment \usepackage{ocamldoc} in manual.tex

If apidoc.tex is ever included in manual, this line should be
uncommented and manual.pdf should depend on apidoc.tex in Makefile

doc/manual.tex

@@ -24,7 +24,7 @@
 %\makeglossaries
 
 % for ocamldoc generated pages
-\usepackage{ocamldoc}
+%\usepackage{ocamldoc}
 \let\tt\ttfamily
 \let\bf\bfseries
 
@@ -149,7 +149,7 @@ are the following.
 
 \item More generic handling of goals and lemmas to prove
   \begin{itemize}
-  \item concept of proof task 
+  \item concept of proof task
   \item generic concept of task transformation
   \item generic approach for communicating with external provers
   \end{itemize}