GUI-1304: Refactor routes to include the bucket name as a matched URL param

... to allow the subpath to be a consistent prefix.

Implements https://eucalyptus.atlassian.net/browse/GUI-1304

Also includes the following changes…
* Fix Paste Object operation when Copy Object menu item is clicked from the bucket contents table view.
* Use consistent code for breadcrumbs across bucket contents and object details page.