Add two missed optional request parameters

There are two optional request parameters missed in
"Create a load balancer health monitor" call as below:
"http_method (Optional)"and "admin_state_up(Optional)".

there also is a mistake for the request parameter "tenant_id".
It should be "Optional",but now it's not.
and the description of "tenant_id" has mistake for VIP.

I added the two request parameters and correct the mistakes.
Closes-Bug:1495229

Change-Id: Ib6263d4770007e0e729ab085e64a2ba23d06a4a9

api-ref/src/wadls/netconn-api/src/common.ent

@@ -2711,13 +2711,13 @@ router.</para>
     </wadl:doc>
 </param>' >
 <!ENTITY hmCreateRequestParams '
-<param xmlns="http://wadl.dev.java.net/2009/02" required="true"
+<param xmlns="http://wadl.dev.java.net/2009/02" required="false"
     name="tenant_id" style="plain" type="csapi:uuid">
     <wadl:doc xmlns="http://docbook.org/ns/docbook"
         xmlns:wadl="http://wadl.dev.java.net/2009/02"
         xml:lang="EN">
         <para>
-          The ID of the tenant who owns the VIP. Only administrative users can
+          The ID of the tenant who owns the health monitor. Only administrative users can
           specify a tenant ID other than their own.
         </para>
     </wadl:doc>
@@ -2757,6 +2757,14 @@ router.</para>
         <para>Maximum consecutive health probe tries.</para>
     </wadl:doc>
 </param>
+<param xmlns="http://wadl.dev.java.net/2009/02" required="false"
+    name="http_method" style="plain" type="xsd:string">
+    <wadl:doc xmlns="http://docbook.org/ns/docbook"
+        xmlns:wadl="http://wadl.dev.java.net/2009/02"
+        xml:lang="EN">
+        <para>The HTTP method that the monitor uses for requests.</para>
+    </wadl:doc>
+</param>
 <param xmlns="http://wadl.dev.java.net/2009/02" required="false"
     name="url_path" style="plain" type="xsd:string">
     <wadl:doc xmlns="http://docbook.org/ns/docbook"
@@ -2772,6 +2780,16 @@ router.</para>
         xml:lang="EN">
         <para>Expected HTTP codes for a passing HTTP(S) monitor.</para>
     </wadl:doc>
+</param>
+<param xmlns="http://wadl.dev.java.net/2009/02" required="false"
+    name="admin_state_up" style="plain" type="xsd:boolean">
+    <wadl:doc xmlns="http://docbook.org/ns/docbook"
+       xmlns:wadl="http://wadl.dev.java.net/2009/02" xml:lang="EN">
+       <para>
+        The administrative state of the health monitor, which is up
+        (<code>true</code>) or down (<code>false</code>).
+       </para>
+    </wadl:doc>
 </param>' >
 <!ENTITY hmUpdateRequestParams '
 <param xmlns="http://wadl.dev.java.net/2009/02" required="true"