This PR makes it possible to set custom headers, in particular for two scenarios:
- geth attach
- geth commands which can use --remotedb, e..g geth db inspect
The ability to use custom headers is typically useful for connecting to cloud-apis, e.g. providing an infura- or alchemy key, or for that matter access-keys for environments behind cloudflare.
Co-authored-by: Felix Lange <fjl@twurst.com>
