doc: Improve some grammar and sentences

90fbf7c has taken care of that for HEAD.  This includes the portion of
the fixes that applies to the documentation, where needed depending on
the branch.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20201227202604.GC26311@telsasoft.com
Backpatch-through: 9.5

diff --git a/doc/src/sgml/ref/pg_dump.sgml b/doc/src/sgml/ref/pg_dump.sgml
index 9c29e39e63caa89982b374cbbd981598bf1c5631..b0b5d6c70c1737e85a242b2c7f374a88bddaf34f 100644 (file)
--- a/doc/src/sgml/ref/pg_dump.sgml
+++ b/doc/src/sgml/ref/pg_dump.sgml
@@ -640,7 +640,7 @@ PostgreSQL documentation
       <listitem>
        <para>
         Specify the compression level to use.  Zero means no compression.
-        For the custom archive format, this specifies compression of
+        For the custom and directory archive formats, this specifies compression of
         individual table-data segments, and the default is to compress
         at a moderate level.
         For plain text output, setting a nonzero compression level causes