Add network.vxlan.mode to agent.properties

Make sure there is an example in the agent.properties file so people
can easily discover this configuration setting exists

Author: wido

agent/conf/agent.properties

@@ -364,6 +364,14 @@ iscsi.session.cleanup.enabled=false
 # to the directory "/usr/share/cloudstack-common/".
 #network.scripts.dir=scripts/vm/network/vnet
 
+# Sets the VXLAN networking mode used, either 'multicast' (default) or 'evpn'.
+# The different modes lead to different scripts being executed by the Agent.
+# multicast: modifyvxlan.sh
+# evpn: modifyvxlan-evpn.sh
+# Existing environments using VXLAN can safely switch to the 'evpn' mode as this
+# will not break existing functionality.
+#network.vxlan.mode=multicast
+
 # Defines the location for storage scripts.
 # The path defined in this property is relative.
 # To locate the script, ACS first tries to concatenate