Make order form functional

[lukechilds]

This makes the buy and sell order forms functional.

Currently the error handling is pretty naive but I don't think that's important right now. We should probably grey out the order form if there is already a pending trade but we aren't storing the trade history so no way to do that yet.

Also, currently the trade is just logged to the console. It should be pushed into a local DB and kept in sync with mm based on the event stream. However this is gonna take a while to get working reliably so I'll add trade history in a follow up PR.

[sindresorhus]

I tried buying without any funds and got this message:

cant find a deposit that is close enough in size. make another deposit that is just a bit larger than what you want to trade

Can we improve those messages directly in mm? https://github.com/jl777/SuperNET/blob/c564d5f61267d6d844864a8efc9cfa7d01a7a29f/iguana/exchanges/LP_ordermatch.c#L1507

[lukechilds]

Can we improve those messages directly in mm?

We could, but bear in mind there are no error codes, only error messages. So changing any error message is potentially a breaking change. Any existing error checking code will break.

e.g our code:

if (result.error === 'only one pending request at a time')

will fail if that message changes. Obviously not ideal, but there's no other way we can target that specific error.

I'll create an issue asking for error codes.

[lukechilds]

jl777/SuperNET#717