Adding Tether as BTCPay Server Foundation supporter about btcpayserver

[rockstardev]

OK, I think I got everything covered with these changes. I will check tomorrow on dev call with @dennisreimann and @pavlenex.

Questions:

• Do we even need assets/tether.svg considering SVG itself is embedded as symbol? (btcpayserver/foundation.btcpayserver.org#32)
• How do we have dynamic theme (dark/light) changing SVGs on READMEs the way we have them on https://foundation.btcpayserver.org ?
  • https://github.com/btcpayserver/btcpayserver
  • https://github.com/btcpayserver/btcpayserver-doc

[dennisreimann]

Do we even need assets/tether.svg considering SVG itself is embedded as symbol?

Practically not. I think the reason those duplicate SVGs exist is due to the fact that we wanted to have them somewhere, but now they should be managed via the design repo: https://design.btcpayserver.org/resources/supporters/

How do we have dynamic theme (dark/light) changing SVGs on READMEs the way we have them on https://foundation.btcpayserver.org/ ?

No, we cannot do that for the READMEs, that's why these SVGs are extra and also share a common format. In cases where the foreground logo doesn't work on both themes, we simply apply a background to the README SVG.