Allow to disable external cache for active-active configuration

nat

#1

For some configurations, you need to turn off the external cache in conntrackd daemon.

Sync {
	Mode FTFW {
		DisableExternalCache On
}

Workaround:

--- ConntrackSync.pm.old	2018-12-21 05:40:24.000000000 +0500
+++ ConntrackSync.pm	2018-12-31 15:52:28.078441250 +0500
@@ -57,7 +57,7 @@
 my $GENERAL_SECTION_START    = "General {\n";
 my $SYNC_SECTION_START       = "Sync {\n";
-my $MODE_SECTION_START       = "\tMode FTFW {\n";
+my $MODE_SECTION_START       = "\tMode FTFW {\n\t\tDisableExternalCache On\n";
 my $MULTICAST_SECTION_START  = "\tMulticast {\n";
 my $UNICAST_SECTION_START    = "\tUDP {\n";
 my $OPTIONS_SECTION_START    = "\tOptions {\n";