collection: Rename all sample playbooks to no longer contain dashes

[berndfinger]

Otherwise, calling a playbook, like the one named sample-sap-hana-preconfigure.yml, as in:

$ ansible-playbook community.sap_install.sample-sap-hana-preconfigure

will fail with an error message which does not immediately show the root cause:

ERROR! the playbook: community.sap_install.sample-sap-hana-preconfigure could not be found

[rhmk]

Playbooks in this directory can be called directly, when they do not contain dashes.
Hence we should recreate the playbooks with the following features:

• flexible hosts entry, which defaults to localhost
• interactive questioning for minimum viable parameters (vars_prompt), if not defined with -e on the cli
• printout of help page / link to all possible parameters

[rhmk]

Wishlist of playbooks, please add more

• sap_hana_preconfigure (run's roles to prepare for SAP HANA)
• sap_netweaver_preconfigure (run's roles to prepare for SAP_NETWEAVER)
• sap_hana_install (run's roles to install SAP HANA)
• optional: sap_s4hana_install (run's role to install S4 HANA)
• optional: sap_hana_uninstall
• optional: sap_s4hana_uninstall