Sequences of fabric configuration steps in the guide need to be fixed

With the current POD fabric configuration guide https://guide.opencord.org/appendix_basic_config.html Users need to jump between sections to complete all the configurations.

Specifically, after updating new IP for compute nodes on leaf-2 in "Configure the Compute Nodes" section, users need to jump to "Connect the Fabric Switches to ONOS" section and and make sure switches are connected to ONOS and then all new IP addresses are updated. Otherwise users cannot proceed since the route changes requires the new IP addresses to be on the compute nodes.