setup: Consider `emacs23' to be an acceptable Emacs.

Prefer `emacs22', because the byte compiled code seems upwards
compatible.

diff --git a/setup b/setup
index 42c0cd7..162ede5 100755 (executable)
--- a/setup
+++ b/setup
@@ -240,7 +240,7 @@ echo "      all done."
 
 $echon "Finding a suitable emacs:$echoc"
 emacs=no
-for i in emacs22 emacs21 emacs; do
+for i in emacs22 emacs23 emacs21 emacs; do
   if type -p >/dev/null $i; then
     emacs=$i
     break