Get inspiration from hashicorp's vault

[fzaninotto]

https://www.vaultproject.io/

Mush more robust and advanced, but similar in many points.

That also means that the REAME should underline the differences with Vault (simpler, serverless, ?)

[Kmaschta]

Google + Hashicorp: https://cloudplatform.googleblog.com/2017/09/HashiCorp-and-Google-expand-collaboration-easing-secret-and-infrastructure-management.html