Include documentation and/or examples on how to add versions to dependencies

[JJ]

Which are apparently used by just a few anyway, but good to know

[jonathanstowe]

Sounds reasonable, I really ought to eat my own dog food on that but every time I've tried to specify a version of dependency it hasn't worked out that well :-O

[JJ]

This seems to work :-) https://github.com/perl6/doc/blob/master/META6.json

[jonathanstowe]

I think my confusion arose because at one point the syntax of the dependencies and actually in the "use" statement weren't consistent. But it seems okay now.