Resolves #164 "Create Service Definition for NST IA Lab Allocation"

The most basic info should all be there (e.g. ACN server names), the rest is/will be in the Confluence page that is linked to in here.

As before, since this is a world-visible Guidebook, I'm deliberately leaving out individuals' names/CRSIDs; Confluence seems like a better place to put that. Nevertheless, the NST Co-ordinator's role address and a reference to infra-sas are world-visible here.

Finally, I deliberately started a new subtree in the sidebar menu as the replacement NST project will need somewhere to live.