Add just some simple way to filter out tokens

For Arbitrum launch we have one issue, most of the bridged tokens don't have liquidity.

This creates a bad user experience.

This PR allows the script generators to provide a filtering function that will have the last call on which token should be included and which don't.

In this simplistic implementation, I just allow to cherry-pick a bunch of tokens by token symbol. I know..., token symbols are not unique, but this comes from know lists so its not expected to have duplicates, and the configuration feels simpler to read if I can select the tokens to include by token symbol

Important

This PR should not be merged, and the token selection is not final. Chen is deciding on the final list of tokens to include, tomorrow he will provide them, so we can launch with a filtered list.

Edit 04/06/2024

I did a bunch of enhancements for the launch. Some of them need to be iterated later.

The goal was to reduce the list to a bunch of meaningful tokens (chen provided the list)

The problem, some of these were not in our list Another problem was that these tokens provided by chen in a CSV didn't have a lot of the information (token name, decimals, etc)

This PR added:

Possibility to add a list of tokens not in the reference list (so you can add tokens even if they are not in coingecko, this way we add the ones picked by chen)
Utility to read the token list from a CSV
Get ERC20 info from onchain, so we can enhance the tokens
Utilities to merge token information, this way we can merge CSV, the token list, and the on-chain data properly
Additional filters: for it was preferred a smaller list of meaningful tokens (instead of a big list of illiquid tokens), therefore an additional filter was provided (the implementation is, that any token not in the CSV is discarded)

cowprotocol / token-lists

Add just some simple way to filter out tokens #398

Important

Edit 04/06/2024