Bug: Issue interacting with Sparrow using Bitcoind backend

[kornpow]

Describe the bug When using Sparrow wallet to connect to the generated bitcoind node, Sparrow adds a wallet folder into the bitcoind node. This ends up causing an error in Polar

To Reproduce Steps to reproduce the behavior:

1. Create a polar network
2. Link Sparrow wallet to bitcoind using rpc
3. Start mining blocks in Polar
4. Get error:
5. 

Expected behavior I should be able to connect Sparrow to bitcoind without interferring with the mining function

Screenshots If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Linux Ubuntu 12.10
• Polar Version: current master branch: yarn dev

Additional context Add any other context about the problem here.

This doesnt help bitcoin-cli unloadwallet "sparrow"

Deleting the Sparrow wallet and then loading the default wallet helps bitcoin-cli loadwallet ""

I also tried unloading the default bitcoind wallet, and only having the Sparrow wallet, and tried to mine block to there, which would be a lot easier. But I get this error:

[kornpow]

Trying to export the internal wallet like this: bitcoin-cli dumpwallet "/home/bitcoin/.bitcoin/test1234.txt" and import the xpriv into Sparrow, but I dont see the mined transactions...

[rolznz]

As soon as I connect Sparrow to Polar it seems to kill Polar's connection to Bitcoind.

I worked around it by using the Polar RPC api via postman, and using the default wallet which is "" (all POST requests to http://127.0.0.1:18443/wallet/)

The polar application is completely unusable but at least I can play around with the RPC API to mine blocks, send bitcoin to a sparrow address and create transactions in sparrow