Adding Toc for the "longish" spec pages.

[tipdbmp via Digitalmars-d-learn]

It seems to me that some of the language reference/spec pages 
that are somewhat long,
could provide a Toc (Table of contents) which should help users 
see an overview of what's
there and improve the searchability and the navigation of the 
content.
The 'Functions' page has a Toc already.