unbreak enter in second wizard step in IE8

Change-Id: I43dabe0242faf41e620e5d34d845934a927dc3a7
Reviewed-on: http://review.couchbase.org/11794
Reviewed-by: Steve Yen <steve.yen@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>

priv/public/index.html

@@ -1296,7 +1296,7 @@ <h2 class="question">Join Cluster / Start new Cluster</h2>
     be inherited by all servers subsequently joining the cluster and it cannot be
     modified in an existing cluster, so please set appropriately.
     </p>
-    <form id="init_cluster_form" class="form block"><input type="submit" style="width:0px; height: 0px; visibility: hidden;">
+    <form id="init_cluster_form" class="form block"><input type="submit" style="width:0px; height: 0px;">
       <div class="pat_10">
          <label>
            <input type="radio" name="join_cluster" id="no-join-cluster" checked />