Missing "Overview" link on the snappy landing page

[David Planella]

All of our landing pages have an "Overview" link in the breadcrumb section that shows the default content of the page. Whenever another breadcrumb link is clicked, the relevant page is shown and its link is highlighted. The snappy section behaves differently for some reason.

Is it because of the renaming we do for Core > Snappy?

Expected:
1. Go to https://developer.ubuntu.com/en/snappy. The breadcrumb section should look like this:

Core > *Overview* | Install | Porting | Guides

2. Click on "Install" (https://developer.ubuntu.com/en/snappy/install). The breadcrumb section should look like this:

Core > Overview | *Install* | Porting | Guides

(See https://developer.ubuntu.com/en/scopes/ (landing page) and https://developer.ubuntu.com/en/scopes/api/ (section with no children) for an example of how this works on the rest of the site)

Actual:
1. Go to https://developer.ubuntu.com/en/snappy. The breadcrumb section looks like this (missing "Overview"):

Core > Install | Porting | Guides

2. Click on "Install" (https://developer.ubuntu.com/en/snappy/install). The breadcrumb section looks like this (all links from the breadcrumb section replaced by a single "Overview" link now):

Core > Overview