Correct hard coded URL, implement missing features

app/assets/stylesheets/desktop/header.scss

@@ -77,4 +77,3 @@ and (max-width : 570px) {
   max-height: 500px;
   overflow: auto;
 }
-

config/locales/server.en.yml

@@ -2154,7 +2154,7 @@ en:
       </p>
       <h2>Search with Google</h2>
       <p>
-        <form action='//google.com/search' id='google-search' onsubmit="document.getElementById('google-query').value = 'site:https://meta.discourse.org ' + document.getElementById('user-query').value; return true;">
+        <form action='//google.com/search' id='google-search' onsubmit="document.getElementById('google-query').value = 'site:' + window.location.host + ' ' + document.getElementById('user-query').value; return true;">
           <input type="text" id='user-query' value="">
           <input type='hidden' id='google-query' name="q">
           <button class="btn btn-primary">Google</button>

lib/search.rb

@@ -154,7 +154,10 @@ class Search
           @status = :archived
           nil
         elsif word == 'status:noreplies'
-          @no_replies = true
+          @posts_count = 1
+          nil
+        elsif word == 'status:singleuser'
+          @single_user = true
           nil
         elsif word == 'order:latest'
           @order = :latest
@@ -294,10 +297,14 @@ class Search
         posts = posts.where('topics.closed')
       end
 
-      if @no_replies
+      if @single_user
         posts = posts.where("topics.featured_user1_id IS NULL AND topics.last_post_user_id = topics.user_id")
       end
 
+      if @posts_count
+        posts = posts.where("topics.posts_count = #{@posts_count}")
+      end
+
       if @user_id
         posts = posts.where("posts.user_id = #{@user_id}")
       end