[Cumulative configs] New settings `override` and `default` about vike

[bighorik]

I would like to be able to flexibly configure this inheritance.
In my practice, a situation often happens when, for example, there are three pages:
applications/listing
applications/favorite
applications/create

For the first two, you need to use a common complex Layout, for the latter, a simpler layout. Accordingly, I would like to be able to set my own Layout for /create, overwriting the original one.

However, there are also reverse situations when you need to specify the Layout for 1 of the many pages, for example:
personalAccount/profile
personalAccount/settings
personalAccount/companies/portfolio
personalAccount/companies/stats
personalAccount/companies/about

In this case, I have added additional navigation for pages /companies - the ability to inherit previous Layouts is great

[brillout]

@bighorik Yeah, currently the only way is to do this:

applications/(complex-layout)/listing
applications/(complex-layout)/favorite
applications/(simple-layout)/create

Let me know whether it's a showstopper for you and I'll bump the priority of this ticket.