Several scripts for Ubuntu to create a Pi Cluster with Hadoop to run a count example

Download and copy hadoop-3.3.6.tar.gz and jdk-8u371-linux-aarch64.tar.gz into the ./dependencies folder.

Afterwards start with the 00_physical_cluster_setup.md file. The order how you suppose to read the READMEs is

1. 00_physical_cluster_setup.md
2. 01_ubuntu_connection_to_pi_cluster.md, 01_windows_connection_to_pi_cluster.md or 01_mac_connection_to_pi_cluster.md
3. 01_ubuntu_internet_sharing.md, 01_windows_internet_sharing.md or 01_mac_internet_sharing.md
4. 02_adding_pi_os_to_sd_cards.md
5. 02_cluster_network.md
6. 02_cluster_passwordless_ssh_and_environment_variables.md
7. 03_hadoop_dependencies.md
8. 03_hadoop_installation.md
9. 03_hadoop_settings.md
10. 03_hadoop_word_count_example.md
11. 04_monitoring_install_node_exporter.md
12. 04_monitoring_install_prometheus.md
13. 04_monitoring_install_v_grafana.md
14. 04_monitoring_visual_dashboard_setup.md
15. 05_nfs_head_node.md
16. 05_nfs_worker_node.md
17. 06_spark_setup.md
18. 07_pyspark_setup.md