* Adding allow route overwrite option
* Add test case for route overwriting after bp copy
* Fix test
* Fix
* Add test case `test_bp_allow_override`
* Remove conflicted future routes when overwriting is allowed
* Improved test test_bp_copy_with_route_overwriting
* Fix type
* Fix type 2
* Add `test_bp_copy_without_route_overwriting` case
* make `allow_route_overwrite` flag to be internal
* Remove unwanted test case
---------
Co-authored-by: Adam Hopkins <adam@amhopkins.com>