Make the template book canon

[monkyyy]

https://github.com/PhilippeSigaud/D-templates-tutorial

Programming in d and the spec are not up to the task for actually 
getting people up to being template wizards. But the template 
book is 10 years out of date and there have been meaningful 
developments in the meantime.

I suggest the following plan of action:

1. someone core-ish and with writing ability forks the project

2. add links to the (forked) book from dlang.org *, the docs of 
std.meta, std.meta.AliasSeq, std.typecons.Tuple, and std.traits.

3. add section to "issues.dlang.org" "Component" field of 
"template book"

4. hope

footnote: links in dlang.org that should link to an (updated?) 
template book

https://tour.dlang.org/tour/en/basics/further-reading
https://tour.dlang.org/tour/en/basics/alias-strings
https://dlang.org/spec/template.html