Add compute node

Adding a new compute node is done through the following few steps:

1. Add the node (my-mgrid2-N) to AD in the server group. N will be the next number that's free.
2. Connect the node to vlan 4003.
3. Ensure PXE network booting is enabled.
4. Power on the machine and watch when it boots into Debian as a new compute node.
5. Log in to the new node as mykopatadmin and run /opt/grid/sbin/init-node-sge