Add HD Wallet integration (temporary and hacky!!!)

Add RPC/Websocket calls for:

getdepositscript
createseries
replaceseries
thawseries
The architecture here makes unit testing very difficult. There's a reason there aren't tests for any of the similar functions here. You need the wallet object which as @gsalgado pointed out, is pretty hard to instantiate. In addition, there's ~20 channels in a wallet object that interact with different go routines and each has a possibility of blocking some function in wallet.

Yes, it's ideal to have unit testing for everything. But this really is a case where it's hard to get the right state for everything before running the function. I'm guessing this is why there aren't unit tests for the many other functions here with the same pattern.

Of course, if you think it can be done, please feel free to have a go at it.