PostgreSQLProvider in non-web hosted applications (Feature #17)

I am writing a WCF service that is not hosted in IIS. In PgMembershipProvider Initialize(....) HostingEnvironment.!ApplicationVirtualPath will always be null.
Because of this WebConfigurationManager.!OpenWebConfiguration(...) will always return the machine config instead of the application config, thus never reading the
machine key settings correctly from the application's configuration.

This can be fixed by checking to see if an ApplicationVirtualPath is present or not, and then opening the application's .exe configuration.

Suggested change PgMembershipProvider.cs line 107:

            Configuration cfg = null;
            if (HostingEnvironment.ApplicationVirtualPath != null)
            {
                cfg = [[WebConfigurationManager]].OpenWebConfiguration(HostingEnvironment.ApplicationVirtualPath);
            }
            else
            {
                // hosted in an application
                cfg = [[ConfigurationManager]].OpenExeConfiguration(ConfigurationUserLevel.None);
            }
            m_machineKeyConfig = (MachineKeySection)cfg.GetSection("system.web/machineKey");

Thanks!
Dan