Improve router

[vadrian89]

The current implementation of the router bacem cluttered and hard to keep track of.
A new implementation is required, one which should:

• create the path automatically
• manage result on pop
• manage modals such as: dialogs and bottom sheet
• manage and make use of query parameters
• use BLoC to handle the state
• be easy to turn into a package for others to use
• be easy to extend