Fix hidden field of PARAM tag description.

git-svn-id: https://klish.googlecode.com/svn/trunk@209 0eaa4687-2ee9-07dd-09d9-bcdd2d2dd5fb

clish.xsd

@@ -245,8 +245,9 @@
 *           feature is implemented to support subcommands with the
 *           same names.
 *
-* [visibility] - define the visibility of the parameter while ${__line}
+* [hidden]  - define the visibility of the parameter while ${__line}
-*           and ${__params} auto variables expanding.
+*           and ${__params} auto variables expanding. The allowed values
+*           is "true" and "false".
 ********************************************************
     -->
     <xs:simpleType name="bool_t">