remove mailing platform/pricing references

[psugihara]

Sofn inc no longer aims to monetize this project. I want to continue maintaining this (with community support) as a totally free and open source project.

Let's remove pricing/platform references from

• web
• docs
• remove whiteglove site

cc @elliothursh @alexfarrill @monicakogler 🤗

[mrlopezco]

<3