Expose add and remove function from the router trie

[anuragsoni]

Right now we have the add function inside the router module that can be used to add a new route to the trie. We should expose that as part of the public API so users can update the router by adding content themselves. On the same topic, maybe we should also implement and expose a remove function.

[anuragsoni]

Closing for now as I'm not sure this will be a really common usecase.