Provide better Ropsten testnet wallet faucet instructions

[BenjaminMoe]

Getting a local ropsten testnet Element node running depends on being able to get developer funds for Ropsten. Right now the documentation points to faucets that might not be funding. So we need to find a better solution for providing test funds specifically for developers setting up an Element node.

Input about this is appreciated.

[bumblefudge]

I would just state in the docs that many faucets exist and to google for more if the first 2 aren't working? and maybe to email whatever@transmute if that fails too, as fallback?

[zkwzk]

I use this https://faucet.metamask.io/ to fund some eth for the Ropsten testnet