Improved thread safety

Ntp.Analyzer.Process/Main.cs

@@ -23,7 +23,9 @@
 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
+
 using System;
+using System.Threading;
 using Ntp.Process;
 using Ntp.Analyzer.Log;
 using Ntp.Monitor.Server;
@@ -59,7 +61,7 @@ namespace Ntp.Analyzer.Process
 
                 foreach (Listener l in i.Listeners)
                     l.Close ();
-                
+
                 LogFactory.Cleanup ();
             }
         }