* add logging functionality for aligning key value pairs after the main messages
* move to own crate, change default message width to 40
* use FullFormat in validator_client (CompactFormat is not compatible with aligning)
* move logging to eth2/utils/logging
- Custom datadir/server argument logic moved into configuration, out of main.
- Updated the validator config directory structure, as per issue #253 suggestions
- Removed the 'generate 3 random keys' function
- Updated the README to reflect new structure
- Just exit if there are no keys, don't generate any (this is for accounts_manager, in a separate commit).
- Created a lib.rs file, so that the validator client configuration can be included by external crates.
- Creates a keystore directory in the config
- Fetches serialized keys from the keystore directory
- If no keys, generates keys randomly, saves serialized keys to keystore dir.
This is a massive commit which restructures the workspace, adds a very
basic, untested, validator client and some very basic, non-functioning
gRPC endpoints to the beacon-node.
