[SEC] Regulations may require to create a light-client for US citizens

**Is your feature request related to a problem? Please describe.**
Given recent public statements of the SEC, the bitshares development community in general as well as the bitshares-ui team in particular should take additional steps to prevent SEC enforcement from going after developers.

**Describe the solution you'd like**
Given that the frontend is independent of the backend (ofc), there is no way we can prevent users to connect any program to a backend and thus have the exchange exposed to U.S. citizens (which is what bothers the SEC).

My first thought would be to release two versions of the software:
* for US-citizens (does not come with the exchange route)
* non-US-citizens (full shebang)

### additional infomation
[SEC public statement](https://www.sec.gov/news/public-statement/digital-asset-securites-issuuance-and-trading)

Start by reviewing how the frontend is separated from the backend and where the exchange route is exposed. Clarify the regulatory requirements and define what the US-citizen version must omit and what the non-US version must retain before implementation.

Written by the indexing model from the issue text.