A more high-level introduction

[yaronf]

Since this is the core document of the working group, I think the Intro should start with a much simpler paragraph saying what this is all about. Here's a shot at it:

Modern financial and commercial networks often transfer digital assets between individuals and companies. Digital assets have many forms, including cryptocurrencies, fiat money equivalents such as CBDC, titles that represent ownership of physical assets and more. Numerous networks exist that allow to transfer such assets between network members, but interoperability between networks barely exists. The goal of the SAT Protocol is to enable digital asset transfer between networks, regardless of the networks' internal structure and technology.

[findthomas]

Thanks Yaron.

[yaronf]

Reopening per my comment to #5 (otherwise please close this issue).