## Proposed Changes
* Add `lcli state-root` command for computing the hash tree root of a `BeaconState`.
* Add a `--network` flag which can be used instead of `--testnet-dir` to set the network, e.g. Mainnet, Goerli, Gnosis.
* Use the new network flag in `transition-blocks`, `skip-slots`, and `block-root`, which previously only supported mainnet.
* **BREAKING CHANGE** Remove the default value of `~/.lighthouse/testnet` from `--testnet-dir`. This may have made sense in previous versions where `lcli` was more testnet focussed, but IMO it is an unnecessary complication and foot-gun today.
