Change references to Ethereum to reference Gnosis

[crtahlin]

Summary

Bee references Ethereum, while Gnosis blockchain is used.

Motivation

References to Ethereum, when Gnosis is used, are at least confusing and can be misleading - a user might work with the Ethereum blockchain, not understanding why things do not work. Funds might be lost.

See screenshot of log output, for an example:

Implementation

Change all references to Ethereum to Gnosis. (Not only what is on screenshot, but wherever relevant.)

Drawbacks

No drawbacks.