Move to YAML config and allow split functions

1. Move to a YAML-based configuration format instead of the original
   INI-based configuration to facilitate better organization and
   readability.
2. Modify the daemon to be able to operate in several modes based
   on configuration flags. Either networking or storage functions
   can be disabled using the configuration, allowing the PVC system
   to be used only for hypervisor management if required.

node-daemon/pvcd/NodeInstance.py

@@ -66,10 +66,18 @@ class NodeInstance(object):
         self.memalloc = 0
         self.vcpualloc = 0
         # Floating upstreams
-        self.vni_dev = self.config['vni_dev']
-        self.vni_ipaddr, self.vni_cidrnetmask = self.config['vni_floating_ip'].split('/')
-        self.upstream_dev = self.config['upstream_dev']
-        self.upstream_ipaddr, self.upstream_cidrnetmask = self.config['upstream_floating_ip'].split('/')
+        if self.config['enable_networking']:
+            self.vni_dev = self.config['vni_dev']
+            self.vni_ipaddr, self.vni_cidrnetmask = self.config['vni_floating_ip'].split('/')
+            self.upstream_dev = self.config['upstream_dev']
+            self.upstream_ipaddr, self.upstream_cidrnetmask = self.config['upstream_floating_ip'].split('/')
+        else:
+            self.vni_dev = None
+            self.vni_ipaddr = None
+            self.vni_cidrnetmask = None
+            self.upstream_dev = None
+            self.upstream_ipaddr = None
+            self.upstream_cidrnetmask = None
         # Flags
         self.inflush = False
 
@@ -240,25 +248,27 @@ class NodeInstance(object):
 
     # Routing primary/secondary states
     def become_secondary(self):
-        self.logger.out('Setting router {} to secondary state'.format(self.name), state='i')
-        self.logger.out('Network list: {}'.format(', '.join(self.network_list)))
-        time.sleep(1)
-        for network in self.d_network:
-            self.d_network[network].stopDHCPServer()
-            self.d_network[network].removeGateways()
-        self.removeFloatingAddresses()
-        self.dns_aggregator.stop_aggregator()
+        if self.config['enable_networking']:
+            self.logger.out('Setting router {} to secondary state'.format(self.name), state='i')
+            self.logger.out('Network list: {}'.format(', '.join(self.network_list)))
+            time.sleep(1)
+            for network in self.d_network:
+                self.d_network[network].stopDHCPServer()
+                self.d_network[network].removeGateways()
+            self.removeFloatingAddresses()
+            self.dns_aggregator.stop_aggregator()
 
     def become_primary(self):
-        self.logger.out('Setting router {} to primary state'.format(self.name), state='i')
-        self.logger.out('Network list: {}'.format(', '.join(self.network_list)))
-        self.createFloatingAddresses()
-        # Start up the gateways and DHCP servers
-        for network in self.d_network:
-            self.d_network[network].createGateways()
-            self.d_network[network].startDHCPServer()
-        time.sleep(0.5)
-        self.dns_aggregator.start_aggregator()
+        if self.config['enable_networking']:
+            self.logger.out('Setting router {} to primary state'.format(self.name), state='i')
+            self.logger.out('Network list: {}'.format(', '.join(self.network_list)))
+            self.createFloatingAddresses()
+            # Start up the gateways and DHCP servers
+            for network in self.d_network:
+                self.d_network[network].createGateways()
+                self.d_network[network].startDHCPServer()
+            time.sleep(0.5)
+            self.dns_aggregator.start_aggregator()
 
     def createFloatingAddresses(self):
         # VNI floating IP