Use UTF-8 for diagnostic output if it is available. Added a command line

switch --no-utf8 to disable the use of UTF-8 characters.

src/ca65/enum.c

@@ -41,6 +41,7 @@
 #include "condasm.h"
 #include "enum.h"
 #include "error.h"
+#include "expect.h"
 #include "expr.h"
 #include "macro.h"
 #include "nexttok.h"
@@ -147,7 +148,7 @@ void DoEnum (void)
     }
 
     /* End of enum definition */
-    Consume (TOK_ENDENUM, "'.ENDENUM' expected");
+    Consume (TOK_ENDENUM, "`.ENDENUM' expected");
 
     /* Free the base expression */
     FreeExpr (BaseExpr);