Remove superflous equal sign (#126)

and traling spaces while at it

book/troubleshooting/crumb-structures/crumb-structures.tex

@@ -14,7 +14,7 @@ that you can use to debug your baking process.
   \label{fig:crumb-structures-book}
 \end{figure}
 
-\subsection{Perfect fermentation}=
+\subsection{Perfect fermentation}
 
 \begin{figure}
   \includegraphics[width=\textwidth]{open-crumb}