registrar: added note about branch flags in save()/lookup() doc

(cherry picked from commit f2996bf)

src/modules/registrar/doc/registrar_admin.xml

@@ -1154,7 +1154,8 @@ kamcmd cfg.set_now_int registrar use_expired_contacts 0
 		modify location records (in usrloc) depending on Contact and Expires header fields in the 
 		REGISTER message. On success and when called from the REQUEST_ROUTE, 
 		<quote>200 OK</quote> will be returned listing all contacts that are currently in 
-		the location database. On an error, an error message will be sent with a short
+		the location database. As a side effect, also branch flags are
+        stored in usrloc. On an error, an error message will be sent with a short
 		description in reason phrase.
 		</para>
 		<para>Meaning of the parameters is as follows:</para>
@@ -1255,6 +1256,7 @@ save("location", "0x00", "sip:test@kamailio.org");
 		Request-URI will be overwritten with the contact that has
 		the highest q value and optionally the rest will be appended to 
 		the message (depending on append_branches parameter value).
+        As a side effect, also branch flags are restored from usrloc.
 		</para>
 		<para>
 		If the <varname>method_filtering</varname> option is enabled and