Further updates to health check endpoint docs

 * Remove documentation to the now deprecated One True Health Check™.
   It is too intrusive and too prone to false positives to recommend.
 * Aliveness test is also a health check, and will respond with a 200
   or 503 as of #856

Author: michaelklishin

deps/rabbitmq_management/priv/www/api/index.html

@@ -951,42 +951,10 @@ <h2>Reference</h2>
         <td></td>
         <td class="path">/api/aliveness-test/<i>vhost</i></td>
         <td>
-          Declares a test queue, then publishes and consumes a
-          message. Intended for use by monitoring tools. If everything
-          is working correctly, will return HTTP status 200 with
-          body: <pre>{"status":"ok"}</pre> Note: the test queue will
-          not be deleted (to prevent queue churn if this is
-          repeatedly pinged).
-        </td>
-      </tr>
-      <tr>
-        <td>X</td>
-        <td></td>
-        <td></td>
-        <td></td>
-        <td class="path">/api/healthchecks/node</td>
-        <td>
-          Runs basic healthchecks in the current node. Checks that the rabbit
-          application is running, channels and queues can be listed successfully, and
-          that no alarms are in effect. If everything is working correctly, will
-          return HTTP status 200 with body: <pre>{"status":"ok"}</pre> If
-          something fails, will return HTTP status 200 with the body of
-          <pre>{"status":"failed","reason":"string"}</pre>
-        </td>
-      </tr>
-      <tr>
-        <td>X</td>
-        <td></td>
-        <td></td>
-        <td></td>
-        <td class="path">/api/healthchecks/node/<i>node</i></td>
-        <td>
-          Runs basic healthchecks in the given node. Checks that the rabbit
-          application is running, list_channels and list_queues return, and
-          that no alarms are raised. If everything is working correctly, will
-          return HTTP status 200 with body: <pre>{"status":"ok"}</pre> If
-          something fails, will return HTTP status 200 with the body of
-          <pre>{"status":"failed","reason":"string"}</pre>
+          Declares a test queue on the target node, then publishes and consumes a
+          message. Intended to be used as a very basic health check.
+          Responds a 200 OK if the check succeeded,
+          otherwise responds with a 503 Service Unavailable.
         </td>
       </tr>
       <tr>