Changes:
- Added `/start`, a page where users can choose whether to run a local
demo of Fleet, or purchase a Fleet Premium license
- Updated all "Try it now" links to go to the `/register` page.
- Updated the URL and added redirects:
- `/customers/new-license` » `/new-license`
- `/try-fleet/fleetctl-preview` » `/try-fleet`
- `/customers/register` » `/register`
- `/customers/login` » `/login`
- Removed the `/try-fleet/login` and `/try-fleet/register` pages
- Updated the /try-fleet/explore-data pages to redirect logged-out-users
to the /register page
- Updated policies, routes, and importer.less
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Co-authored-by: Mike Thomas <78363703+mike-j-thomas@users.noreply.github.com>
