change default display of nav menu to no-hide

[uvtc]

When I first opened up the docs for Janet, I thought, "weird, where's the nav menu?" After some searching around I discovered it (Ah! The triple-decker icon button opens it!).

Then, days later, I took a look at the Mendoza docs, and thought, "weird, deja vu, where's the nave menu?". :) Found it more quickly this time. But still...

Consider making the default to display the nave menu, then users can hide it later if they wish.

I don't have the link, but also saw someone post on HN about having trouble navigating the Janet docs until someone told them to click the hamburger button or somesuch to bring un-hide the nav menu (sorry, don't have the link).