Initial accordeon state

This adresses #705 

Note that it implements the proposal by @cedricmoullet 

It's only applied during loading of the application. No additional functionality.

Catalog accordion is always open.
If permalink contains layers, then layer manager accordion is open.

When on mobile, neither of those are open on start.

I'm not completely happy with this PR, but because boostrap seperates the toggler and the togglee, this is the only sensible solution I found, after quite some playing around. Maybe others will have a better approach.