Expand "Getting Started" to fully explain security requirements

[gary-rowe]

User feedback has indicated that the following questions arise in the mind of someone unfamiliar with Bitcoin wallets in relation to wallet words:

• Why do I have these?
• Under what circumstances will I need them?
• What happens if I lose them?
• Why these words and why can't I choose them myself?

A suggested workflow is "How to Install (OS-specific) -> Getting started -> Run up the application"

[gary-rowe]

Revisiting the help indicates that this is all covered in the "create-wallet" article.

Closing.