Land #3184, Rex::Proto::Http::Client IOError fix

lib/rex/proto/http/client.rb

@@ -198,7 +198,7 @@ class Client
   def close
     if (self.conn)
       self.conn.shutdown
-      self.conn.close
+      self.conn.close unless self.conn.closed?
     end
 
     self.conn = nil

spec/lib/rex/proto/http/client_spec.rb

@@ -112,6 +112,7 @@ describe Rex::Proto::Http::Client do
       conn.stub(:put)
       conn.stub(:shutdown)
       conn.stub(:close)
+      conn.stub(:closed? => false)
 
       conn.should_receive(:get_once).and_return(first_response, authed_response)
       conn.should_receive(:put) do |str_request|