* Added the RouteUrl type and improved router types
* Added more tests for router types
* Add build test for typescript types
* Add next-env.d.ts to the typescript test
* Removed next-env.d.ts
* Added next-env.d.ts to gitignore
* Remove route url re-exports
* renamed PublicRouterInstance to be NextRouter
* export the Url type
* Replaced BaseRouter with NextRouter in server/utils
* Don't export the Url type
* Update tsconfig.json