Interstitial zerodot File: and Image: links on non-NS_ZERO pages. Fixes bug 55819.

* Currently, File: and Image: links (and their NS localizations) are direct linked in zerodot.
* This patch introduces interstitials for such zerodot hyperlinks.

Change-Id: I4bb0ee9a184f58a8ad0290d064517d73534476fa
Merge "Interstitial zerodot File: and Image: links on non-NS_ZERO pages. Fixes bug 55819."