oracle for v1 AMM pools

[tjcloa]

The Sovryn Swap Network allows the trading of assets with or without external price feeds. Latter are being managed by v1 pools, where the market is defining the price.
The Sovryn Margin Trading and Lending Protocol, however, requires price feeds for each supported asset. While it would be easy to just query the latest price from the respective v1 pool, it would be prone to oracle price manipulation attacks.
Therefore, it is suggested to create an oracle relying on weighted moving averages (WMA) or exponential moving averages (EMA).
Details:
https://docs.google.com/document/d/1acGmVgz3ZTLuRQRx-82tMIZiNYepvqOWoWvs0k_EIFc/edit