Bt india

Ok, I have made some changes to this feature in order to DRY it up a bit and make it more efficient. There are no longer any repeated/copied snippets, and the changes made for the /custom/* routes do not affect the current routes. For proof of concept, pull down and navigate to /modern, and then /custom/modern in another tab. in an idea world we strip out all of those hardcoded declarations for /modern, /client-solutions, /legacy, etc.

I know several of the UI guys in London are out at the moment, but this is something I need to keep pushing forward with for LP India. Would love for @i-like-robots or @Ianfeather to take a look and let me know your thoughts.
I see what you're doing here. it kinda sucks though :/ Not that that's your fault. Couple of options:

- Leave it as it is for now, merge and deal with it later
- Use a helper just to clean this up so we don't have something so ugly in the view. eg.
```
def show_nav_section(section)
  (defined?(section) && section == true) || (!defined? section)
end
```

- Work out a way of extending this configuration object style to the rest of the layouts before merging