ADDS: adding subheading in deployment_guide.md

doc/deployment_guide/deployment_guide.md

@@ -10,11 +10,12 @@ In this section, we describe how to configure a machine (physical or virtual) to
 **NOTE**: If you already have a remote physical server fitting the requirements specified in this section feel free to use it instead of deploying a local VM. Check [1.1.1. Physical Server](#1-1-1-physical-server) for further details.
 
 Virtualization platforms tested are:
-  - [1.1.1. Physical Server](#1-1-1-physical-server)
-  - [1.1.2. Oracle Virtual Box](#1-1-2-oracle-virtual-box)
-  - [1.1.3. VMWare Fusion](#1-1-1-vmware-fusion)
-  - [1.1.4. OpenStack](#1-1-1-openstack)
-  - [1.1.5. Vagrant Box](#1-1-1-vagrant-box)
+
+- [1.1.1. Physical Server](#1-1-1-physical-server)
+- [1.1.2. Oracle Virtual Box](#1-1-2-oracle-virtual-box)
+- [1.1.3. VMWare Fusion](#1-1-3-vmware-fusion)
+- [1.1.4. OpenStack](#1-1-4-openstack)
+- [1.1.5. Vagrant Box](#1-1-5-vagrant-box)
 
 ## 1.1.1. Physical Server
 This page describes how to configure a physical server for running ETSI TeraFlowSDN(TFS) controller.