Create custom token/coin function, so we no longer have to use NULL1, NULL2, ... NULLx

I think we really need an ability to create custom tokens/coins.

With the massive increase in cryptocurrency platforms, having to rely on NULL1, NULL2,… etc… while waiting for Koinly to add support is a bit messy (for example waiting for Tezos token support)

I’ve got NULL1 through to NULL11 in my wallets, it’s a mess and I would really love the ability to create a custom token that is private to my account, and this would let me track my assets much better.

Thanks for considering.