Raise the version number to 5.1.23,

because we already split off a tree for 5.1.22 to receive only selected fixes.

configure.in

@@ -10,7 +10,7 @@ AC_CANONICAL_SYSTEM
 #
 # When changing major version number please also check switch statement
 # in mysqlbinlog::check_master_version().
-AM_INIT_AUTOMAKE(mysql, 5.1.22-beta)
+AM_INIT_AUTOMAKE(mysql, 5.1.23-beta)
 AM_CONFIG_HEADER([include/config.h:config.h.in])
 
 PROTOCOL_VERSION=10