Volkan,
What I see in the link is the original post.
I did not see any postgres log entry complaining about invalid entry in
pg_hba.conf.
The pg_hba.conf entry in your original post is wrong. What you need is
host replication replication 104.131.66.183/32 md5
If you get an error after making that change, then please attach the
complete new
version of the pg_hba.conf AND the entry from postgres log where it
complains about
the invalid or non pg_hba.conf entry.