memcached: Fix typos in module documentation

src/modules/memcached/doc/memcached_admin.xml

@@ -75,7 +75,7 @@ xlog("stored value is $mct(test)"); # will return <null>
 		This module is an addition to the existing <emphasis>htable</emphasis> functionality,
 		not a replacement. In smaller architectures or installations where only one instance
 		needs access to the hash table the htable module is easier to setup, as no dedicated
-		server needs to be provided. But when a distributed storage facilility is necessary,
+		server needs to be provided. But when a distributed storage facility is necessary,
 		or one want to separate the storage from the SIP server, this module could be used.
 	</para>
 	</section>
@@ -182,7 +182,7 @@ modparam("memcached", "servers", "localhost:11211")
 		</para>
 		<para>
 			It is possible to override this default value when adding a key with the
-			<emphasis>mct</emphasis> psuedo-variable, or later on by setting a different
+			<emphasis>mct</emphasis> pseudo-variable, or later on by setting a different
 			timeout for an existing key with the <emphasis>mctex</emphasis> pseudo-variable.
 		</para>
 		<para>