doc: Markup and formatting improvements

doc/src/sgml/ref/alter_subscription.sgml

@@ -25,11 +25,11 @@ ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> WITH ( <rep
 
 <phrase>where <replaceable class="PARAMETER">option</replaceable> can be:</phrase>
 
-  SLOT NAME = slot_name
+  SLOT NAME = <replaceable class="PARAMETER">slot_name</replaceable>
 
 ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
-ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> CONNECTION 'conninfo'
-ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> SET PUBLICATION publication_name [, ...]
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> CONNECTION '<replaceable>conninfo</replaceable>'
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> SET PUBLICATION <replaceable>publication_name</replaceable> [, ...]
 ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> ENABLE
 ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> DISABLE
 </synopsis>

doc/src/sgml/ref/create_subscription.sgml

@@ -21,13 +21,16 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-CREATE SUBSCRIPTION <replaceable class="PARAMETER">subscription_name</replaceable> CONNECTION 'conninfo' PUBLICATION { publication_name [, ...] } [ WITH ( <replaceable class="PARAMETER">option</replaceable> [, ... ] ) ]
+CREATE SUBSCRIPTION <replaceable class="PARAMETER">subscription_name</replaceable>
+    CONNECTION '<replaceable class="PARAMETER">conninfo</replaceable>'
+    PUBLICATION { <replaceable class="PARAMETER">publication_name</replaceable> [, ...] }
+    [ WITH ( <replaceable class="PARAMETER">option</replaceable> [, ... ] ) ]
 
 <phrase>where <replaceable class="PARAMETER">option</replaceable> can be:</phrase>
 
     | ENABLED | DISABLED
     | CREATE SLOT | NOCREATE SLOT
-    | SLOT NAME = slot_name
+    | SLOT NAME = <replaceable class="PARAMETER">slot_name</replaceable>
 </synopsis>
  </refsynopsisdiv>
 

doc/src/sgml/ref/drop_subscription.sgml

@@ -57,8 +57,8 @@ DROP SUBSCRIPTION [ IF EXISTS ] <replaceable class="parameter">name</replaceable
    </varlistentry>
 
    <varlistentry>
-    <term><replaceable class="parameter">DROP SLOT</replaceable></term>
-    <term><replaceable class="parameter">NODROP SLOT</replaceable></term>
+    <term><literal>DROP SLOT</literal></term>
+    <term><literal>NODROP SLOT</literal></term>
     <listitem>
      <para>
       Specifies whether to drop the replication slot on the publisher.  The