Update the RPC API to the latest bitcoin version.

[kiwiidb]

Hey there,

I am trying to connect C-lightning to spruned, however C-lightning can't connect because:

bcli: Unsupported bitcoind version 150100, at least 160000 required.

[kiwiidb]

Update: I have manually updated the hard-coded version in jsonrpc_server.py. Now lightningd fails with:
bcli: The 'blocksonly' mode of bitcoind, or any option deactivating transaction relay is not supported.

[gdassori]

Hello, the RPC API needs to be updated and compliant with the latest bitcoin version.
I'll work on this.

[suchdatums]

Any progress on this update? I fell off my chair when I discovered this repo - this node software can power some useful projects! But, it's based on bitcoin 0.16 (?) Otherwise, does anyone know of other 'lightweight' node emulators that simply query other nodes when RPC is used?