To more clearly acknowledge that any Electrum-protocol implementation can be configured for address queries, the names of variables explicitly named "ElectrumX" have been changed to "Electrum". Backward compatibility with any clients using the old names is meant to be preserved.
Stop using type=boolean for args via cli since they force the default value false. Rather, use the default-setting code in config.js for both cli args and env vars.
Also add some additional logging to help debugging issues like this in the future
Don't set default for "slowDeviceMode" arg because doing so prevents "dotenv" from setting that value even if it's in your .env file (it's a key design criteria of dotenv to not override any existing value). The default value is already set in config.js, so we're fine just dropping it here.
Move closer to the original vision of supporting any address-querying implementation desired. Current options include ElectrumX (as before) and now blockchain.com and blockcypher.com since they were easy to support and are publicly/easily available (though ridiculously neither is yet to support bc1 addresses).
- new env var option BTCEXP_ADDRESS_API, value can be electrumx, blockchain.com, blockcypher.com
- update ElectrumX client connect to request v1.4 of API as all clients are now supposed to do
- misc frontend improvements/cleanup for addresses
This ensures a unique, hard-to-guess cookie secret for every instance.
Also, renamed from "cookiePassword" to "cookieSecret" to better express
its meaning.
