Add CLI description to the help.sap.com portal

[pPrecel]

Description

Executions:

• Add a short description the about main mission of the Kyma CLI (like it is for the busola)
• Add tutorial about adding module and making it managed/unmanaged using the Kyma CLI (like it is for the busola)
• Place both articles on the cli repo (under the docs folder)

Reasons

Inform users about the main mission of the Kyma CLI and basic functionalities.

Attachments

kyma on sap portal