Doc: Change optional parameters grouping in Create Subscription.
The subscription parameters are rearranged into two groups:
a) those that control what happens during Create Subscription
b) those that control the replication behavior
This makes the documentation of Create Subscription easier to follow.
Author: Peter Smith Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CAHut+PtPJDSOxtuMGpO2yDrRPKxcYGL4n7HqJP9HernZE=Cj+g@mail.gmail.com