pgcrypto's encrypt() supports AES-128, AES-192, and AES-256

Previously, only 128 was mentioned, but the others are also supported.

Thomas Munro, reviewed by Michael Paquier and extended a bit by me.

Discussion: http://postgr.es/m/CAEepm=1XbBHXYJKofGjnM2Qfz-ZBVqhGU4AqvtgR+Hegy4fdKg@mail.gmail.com

contrib/pgcrypto/expected/rijndael.out

 --
--- AES / Rijndael-128 cipher
+-- AES cipher (aka Rijndael-128, -192, or -256)
 --
 -- ensure consistent test output regardless of the default bytea format
 SET bytea_output TO escape;

contrib/pgcrypto/sql/rijndael.sql

 --
--- AES / Rijndael-128 cipher
+-- AES cipher (aka Rijndael-128, -192, or -256)
 --
 -- ensure consistent test output regardless of the default bytea format
 SET bytea_output TO escape;

doc/src/sgml/pgcrypto.sgml

@@ -1062,7 +1062,7 @@ decrypt_iv(data bytea, key bytea, iv bytea, type text) returns bytea
 
   <itemizedlist>
    <listitem><para><literal>bf</literal> &mdash; Blowfish</para></listitem>
-   <listitem><para><literal>aes</literal> &mdash; AES (Rijndael-128)</para></listitem>
+   <listitem><para><literal>aes</literal> &mdash; AES (Rijndael-128, -192 or -256)</para></listitem>
   </itemizedlist>
    and <replaceable>mode</> is one of:
   <itemizedlist>