fix(routing): fix Windows normalize bug

[mtaberna]

The use of normalize function from Node library in Windows return
unexpected backslash when normalizing slug. The use of normalize library
should be completely removed, as a hot fix I added the slash library to
revert Windows backslash.

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[styxlab]

Closing this PR as I am not (yet) ready to support native Windows, If you use Windows, the recommended way is to use this repo on WSL (Windows subsystem for Linux). If anyone wants to make this repo fit for native Windows, I am open to looking into any new proposals, but I will require the following prerequisites:

1. Identify all code places that are potentially broken on native Windows
2. Research into whether problems can be fixed upstream or with standard packages, to keep any windows specific code to the minimum (ideally all packages work on Windows as well)
3. Design some specific tests for Windows, so future problem can be detected early on

Please open a new issue if you want to discuss or continue working on native Windows support.