Various Router Improvements

[Ben-G]

Tackles issues brought up about ReSwiftRouter.

• There is now a dedicated way to set stored data for a specific route (equivalent of calling URL with query parameter, or something similar) as requested in Route with parameters #3
• Router no longer asserts when it is stuck, instead it prints a warning and offers a hook for symbolic breakpoint. This was addressed in When debugging sometimes getting, fatal error: [SwiftFlowRouter]: #12
• Provide the ability to switch a route animated/unanimated as requested in Usage with deep-linking and animations #4