* Move demandDirectoryRoot into kyaml/filesys
* Make root directory platform-agnostic
Support windows root directory. Dogfood own error package.
* Use cleaner windows support implementation
* Address feedback
* Address feedback x2
* Re-apply go.sum changes to avoid CI errors
* Move api/filesys to kyaml/filesys
* Add deprecated version of api/filesys with aliases to new code
* Use new kyaml/filesys package and update dependencies
* Migrate to kyaml/filesys and update dependencies
* Skip tests that break on Windows