Move AllowCascadeReplication() define from xlog.h to replication include

Bruce Momjian <bruce@momjian.us>

Commit: 85e6e1662b2c475a408afc1ea2ddade7974eddbb
Author: Bruce Momjian <bruce@momjian.us>
Date: 2011-09-04T00:46:19Z
Releases: 9.2.0
Move AllowCascadeReplication() define from xlog.h to replication include
file.

Per suggestion from Alvaro.

Files