Rewrite DNSAggregatorInstance to handle DNS well

Trying to directly AXFR from dnsmasq is a mess, since their zone is
barely compliant with spec, it doesn't support notifies, and it is
generally really messy.

This implements an advanced "AXFR parser" system, which looks at the
results of an AXFR from the local dnsmasq instances per-network, and
updates the real replicated MariaDB pdns backend cluster with the
changed data. This allows a sensible, transferable zone with its own
SOA that is dynamically reconfigured as hosts come and go from the
dnsmasq zone.

node-daemon/pvcd/Daemon.py

@@ -116,6 +116,8 @@ staticdata.append(subprocess.run(['uname', '-m'], stdout=subprocess.PIPE).stdout
 # Config values dictionary
 config_values = [
     'coordinators',
+    'cluster_domain',
+    'storage_domain',
     'dynamic_directory',
     'log_directory',
     'file_logging',
@@ -125,6 +127,11 @@ config_values = [
     'successful_fence',
     'failed_fence',
     'migration_target_selector',
+    'pdns_mysql_host',# = 'localhost'
+    'pdns_mysql_port',# = 3306
+    'pdns_mysql_dbname',# = 'pvcdns'
+    'pdns_mysql_user',# = 'pvcdns'
+    'pdns_mysql_password',# = 'pvcdns'
     'vni_dev',
     'vni_dev_ip',
     'vni_floating_ip',
@@ -531,7 +538,7 @@ pool_list = []
 
 # Create an instance of the DNS Aggregator if we're a coordinator
 if config['daemon_mode'] == 'coordinator':
-    dns_aggregator = DNSAggregatorInstance.DNSAggregatorInstance(zk_conn, config, logger, d_network)
+    dns_aggregator = DNSAggregatorInstance.DNSAggregatorInstance(zk_conn, config, logger)
 else:
     dns_aggregator = None
 
@@ -596,9 +603,10 @@ def update_networks(new_network_list):
     for network in new_network_list:
         if not network in network_list:
             d_network[network] = VXNetworkInstance.VXNetworkInstance(network, zk_conn, config, logger, this_node)
+            print(network)
+            dns_aggregator.add_network(d_network[network])
             # Start primary functionality
             if this_node.router_state == 'primary':
-                dns_aggregator.add_client_network(network)
                 d_network[network].createGateways()
                 d_network[network].startDHCPServer()
 
@@ -609,7 +617,7 @@ def update_networks(new_network_list):
             if this_node.router_state == 'primary':
                 d_network[network].stopDHCPServer()
                 d_network[network].removeGateways()
-                dns_aggregator.remove_client_network(network)
+                dns_aggregator.remove_network(d_network[network])
             # Stop general functionality
             d_network[network].removeFirewall()
             d_network[network].removeNetwork()
@@ -896,11 +904,6 @@ def update_zookeeper():
     else:
         ceph_health_colour = logger.fmt_red
 
-    # DNS aggregator retransfer
-    if this_node.router_state == 'primary':
-        for network in d_network: 
-            dns_aggregator.get_axfr(network)
-
     # Set ceph health information in zookeeper (primary only)
     if this_node.router_state == 'primary':
         # Get status info