Ability to remove/hide menu items

Update

@Platoniq implemented this on this module: https://github.com/Platoniq/decidim-module-decidim_awesome/#11-change-the-main-menu-of-decidim-entirely

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@verarojman asked on gitter whether it was possible to somehow remove menu items through the decidim.rb initializer. I investigated a bit and it looks like the menu subsystem is append-only at this point.

It is possible to hide them using CSS/JS hacks, but that's obviously brittle and can have unexpected consequences.

Being able to edit the menu through the initializer (or through the admin dashboard) seems like a sensible expectation from Decidim instance maintainers, to me. And from what I could tell, it's viable to extend the menu subsystem to allow for this within its current architecture.

Not sure how high a priority this would be, of course. Nor how common this demand is.

What do you all think?