Use scalable graphics for hierarchical state machine

Also updating the other state machine figure with the same style.

chapters/statemachines.tex

@@ -468,12 +468,16 @@ \subsection{Merging Connections to Multiple Outputs}\label{merging-connections-t
 
 \subsection{Example}\label{example}
 
-\begin{example}
-Consider the following hierarchical state machine:
-
-\includegraphics[width=5.34375in,height=5.72917in]{statemachine2}
+\begin{figure}[H]
+  \begin{center}
+    \includegraphics{hierarchical-statemachine}
+  \end{center}
+  \caption{Example of a hierarchical state machine.}
+  \label{fig:hierarchical-statemachine}
+\end{figure}
 
-The model demonstrates the following properties:
+\begin{example}
+Consider the hierarchical state machine in \cref{fig:hierarchical-statemachine}.  The model demonstrates the following properties:
 \begin{itemize}
 \item
   \lstinline!state1! is a meta state with two parallel state machines in it.
@@ -484,19 +488,19 @@ \subsection{Example}\label{example}
   \lstinline!outer!. The top level declares \lstinline!v! as \lstinline!inner! and gives the start value.
 \item
   \lstinline!count! is defined with a start value in \lstinline!state1!. It is reset when
-  a reset transition (v\textgreater{}=20) is made to \lstinline!state1!.
+  a reset transition (\lstinline!v >= 20!) is made to \lstinline!state1!.
 \item
   \lstinline!stateX! declares the local variable \lstinline!w! to be equal to \lstinline!v! declared
   as \lstinline!inner input!.
 \item
   \lstinline!stateY! declares a local counter \lstinline!j!. It is reset at start and as a
-  consequence of the reset transition (v\textgreater{}=20) to \lstinline!state1!:
-  When the reset transition ($v\ge 20$) fires, then the variables of the
+  consequence of the reset transition (\lstinline!v >= 20!) to \lstinline!state1!:
+  When the reset transition (\lstinline!v >= 20!) fires, then the variables of the
   active states are reset immediately (so \lstinline!count! from \lstinline!state1!, and \lstinline!i!
   from \lstinline!stateX!). The variables of other states are only reset at the time
   instants when these states become active. So \lstinline!j! in \lstinline!StateY! is reset to
-  0, when the transition \lstinline!stateX.i! \textgreater{} 20 fires (after \lstinline!state1!
-  became active again, so after the reset transition $v\ge 20$).
+  0, when the transition \lstinline!stateX.i > 20! fires (after \lstinline!state1!
+  became active again, so after the reset transition \lstinline!v >= 20!).
 \item
   Synchronizing the exit from the two parallel state machines of
   \lstinline!state1! is done by checking that \lstinline!stated! and \lstinline!stateY! are active using the