ROUTES: As a user I want to be able to use one of my Markers more than once in a Route

[StevenAbrams]

Currently:
A user can add as many markers as they wish. But when the user wants to create a route, they can only add existing markers to their route. In the current version, a route is only allowed to use a Marker once and once only. This makes a route limited.

Proposed:
Allow a user to create a route by using a Marker more than once. For example if the route happens to pass a particular marker more than once, then allow the user to use that Marker again.