cli: transfer whitelisted tokens by symbol.

[palango]

Component

@celo/celocli

Describe the feature you would like

Currently the transfer:* commands do not support USDT or USDC or other fee currencies, just hardcoded values in --stableToken cUSD|cusd|cEUR|ceur|cREAL|creal.

It would be nice to either dynamically fill all available stables there or let the user specify a contract address to use.

$ celocli transfer:stable --from 0xc1912fEE45d61C87Cc5EA59DaE31190FFFFf232d --to 0xc1912fEE45d61C87Cc5EA59DaE31190FFFFf232d --value
    10000000000000000000000 --stableToken cUSD|cusd|cEUR|ceur|cREAL|creal

Additional context

[gastonponti]

For the second part "let the user specify a contract address to use", there is a transfer:erc20 that allows you to add the address of the token you want:
celocli transfer:erc20 --from XXX --to YYY --value ZZZ --erc20Address ERC20_ADDRESS

[aaronmgdr]

hmm maybe some system where we allow any token whitelisted for as gas token to be sent by pulling the whitelist and find which matches the symbol passed in.

what we do not want us anything that requires updating cli when mento changes tokens or the whitelist updates.

[palango]

hmm maybe some system where we allow any token whitelisted for as gas token to be sent by pulling the whitelist and find which matches the symbol passed in.

Yeah, that sounds like a good idea.