Re: doc: create table improvements

hi.

-<phrase>where <replaceable
class="parameter">column_constraint</replaceable> is:</phrase>
+<phrase>where <replaceable>persistence_mode</replaceable> is: </phrase>
+
+[ GLOBAL | LOCAL ] { TEMPORARY | TEMP } |
+UNLOGGED

we can just do it with one line:
[ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED

most of the time, the patch using:
<replaceable>persistence_mode</replaceable>
<replaceable>oversize_storage</replaceable>

for column_constraint we are using
<replaceable class="parameter">column_constraint</replaceable>

do we need change it to
<replaceable class="parameter">persistence_mode</replaceable>
<replaceable class="parameter">oversize_storage</replaceable>
?

I don't know the purpose of this extra ``"class="parameter"``.