Reorganize top-level folders

[shu-mutou]

I suggest organizing top-level folders as follows:

• Keep the remote folder for on-demand self-study and the exercises folder for teaching materials as they are.
• Keep the folder with the OWNERS file managed by the local community as they are.
  • aotearoa
  • brazil
  • india
  • japan
• Create a /events/ folder for past events such as NCW and move them under that.
  • barcelona -> rename to ncw-2019-barcelona
  • bay-area-kube-day -> rename to bay-area-kube-day-2019
  • denver -> rename to gophercon-2018-denver
  • oscon-2019
  • paris -> rename to ossummit-2018-paris
  • presentations/README.md -> rename to ncw-2018-seattle/presentasions.md
  • sandiego -> rename to ncw-2019-sandiego
  • seattle -> rename to ncw-2018-seattle
  • shanghai -> rename to ncw-shanghai
• If there is no OWNERS file and the folders are considered to have no administrator, the contents of the folders will be moved to the remote folder
  • australia
  • austria
  • morocco
• If there is no OWNERS file and no new contributor files, the folders will be deleted
  • beijing

[shu-mutou]

/sig contributor-experience

[k8s-ci-robot]

@shu-mutou: The label(s) sig/contrib-ex cannot be applied, because the repository doesn't have them.

In response to [this](https://github.com/kubernetes-sigs/contributor-playground/issues/1533#issuecomment-2482558774): >/sig contrib-ex > Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes-sigs/prow](https://github.com/kubernetes-sigs/prow/issues/new?title=Prow%20issue:) repository.

[k8s-ci-robot]

@shu-mutou: The label(s) sig/[contributor-experience](https://github.com/kubernetes/kubernetes/labels/sig%2fcontributor-experience) cannot be applied, because the repository doesn't have them.

In response to [this](https://github.com/kubernetes-sigs/contributor-playground/issues/1533#issuecomment-2482565083): >/sig [contributor-experience](https://github.com/kubernetes/kubernetes/labels/sig%2Fcontributor-experience) Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes-sigs/prow](https://github.com/kubernetes-sigs/prow/issues/new?title=Prow%20issue:) repository.

[shu-mutou]

/sig contributor-experience

[shu-mutou]

/assign cblecker jberkus kaslin nikhita