Make gatekeeper's address check case-insensitive.

OpenSim/Services/HypergridService/GatekeeperService.cs

@@ -333,7 +333,8 @@ namespace OpenSim.Services.HypergridService
 
             string addressee = parts[0];
             m_log.DebugFormat("[GATEKEEPER SERVICE]: Verifying {0} against {1}", addressee, m_ExternalName);
-            return (addressee == m_ExternalName);
+
+            return string.Equals(addressee, m_ExternalName, StringComparison.OrdinalIgnoreCase);
         }
 
         #endregion