[class] Add page breaks.

Partially addresses #4228.

Author: Dawn Perchik

source/classes.tex

@@ -1502,6 +1502,7 @@
 };
 X a(1);             // calls \tcode{X(int);}
 X b(a, 0);          // calls \tcode{X(const X\&, int);}
+@\newpage@
 X c = b;            // calls \tcode{X(const X\&, int);}
 \end{codeblock}
 \end{example}
@@ -4438,6 +4439,9 @@
 of a
 derived class to a pointer or reference to one of its base classes shall
 unambiguously refer to a unique object representing the base class.
+
+\newpage
+
 \begin{example}
 \begin{codeblock}
 struct V { };