Fix nullable scope path creation

[sdsd08013]

• problem

If passed Optional scope path like (/:locale)/users(.:format) to Route constructor.

Route instance member @path set value "".

because:
route.path.spec.to_s.split('(') => ["", "/:locale)/users", ".:format)"]

• change

@path = route.path.spec.to_s.sub(/\(.:format\)/, "").delete('(', '').delete(')', '')

this return right path /:locale)/users

plz check it.