Support for neutrino clients

[i5hi]

The specfic update in this PR is at /cyphernodeconf_docker where a bitcoin_cbf property is added to the schema/config-v0.2.5.json and prompters/900_bitcoin.js to allow a user the option to set peerblockfilters=1 to templates/bitcoin/bitcoin.conf to serve compact block filters for neutrino clients.

[i5hi]

This can be tested using:

docker exec -it dist_bitcoin_1 bitcoin-cli getnetworkinfo | jq -r ".localservicesnames"

[
   "NETWORK",
   "WITNESS",
   "COMPACT_FILTERS",
   "NETWORK_LIMITED"
]

[Kexkey]

Thanks for the PR @vmenond ! Sorry for the delay, I was away in the last week or so.

Is the overhead of enabling peerblockfilters a big problem? Do you think it would be a good idea to just enable it by default without asking the user?

[i5hi]

Hey @Kexkey! So sorry about the delay. Just saw your response to this!

There is quite a bit of networking overhead - I haven't tested it but some devs at bdk have and mentioned the overhead can be quite a bit, so might not be a good default.

Will run a few tests on this and share some exact figures.

[Kexkey]

Thanks for your contribution! Can you base your PR on dev? I'd like to try this.