Update copyright generation to work with T1 fontencoding

`\copyright` is not defined in T1 but `\textcopyright`is

Sources:
harveymuddcollege/hmcthesis-class@49495c7
https://tex.stackexchange.com/questions/29895/how-to-get-copyright-when-mixing-t1-fonts-and-fontspec

ucetd.cls

@@ -21,7 +21,7 @@
 % Default copyright text
 \newcommand{\etdCopyrightText}{
 	\null\vfill
-	\centerline{Copyright \copyright\ \number\year\ by \@author}
+	\centerline{Copyright \textcopyright\ \number\year\ by \@author}
 	\centerline{All Rights Reserved}
 	\vskip 15pt\relax
 }