Enhance NFSv4 server and client configuration documentation with installation steps, share maintenance, and user creation instructions

- Created a new markdown file for DNS service configuration, detailing installation, configuration, and testing steps.
- Created a new markdown file for Kerberos authentication service, including DNS configuration, installation, and user management.
- Added a new markdown file for virtualization commands related to DNS and Kerberos utilities, including usage examples for `dig`, `nslookup`, `kinit`, `klist`, `kdestroy`, `kpasswd`, and `kadmin`.

Remove unnecessary blank line before the section on creating a new logical volume in the documentation for Série 0500 - Libvirt + KVM + LVM.

Refactor Commandes.md to enhance command descriptions and examples, improving clarity and usability.

Refactor network configuration documentation for VM3, adding detailed verification steps and persistent routing instructions

Add detailed instructions for creating and managing storage pools and volumes in Libvirt with KVM and LVM