add readme & license (#21)

* add readme

* add license

* fix readme

README.md

@@ -0,0 +1,27 @@
+# <h1 align="center"> reth </h1>
+
+*Blazing-fast implementation of the Ethereum protocol*
+
+![Github Actions](https://github.com/foundry-rs/reth/workflows/ci/badge.svg)
+
+## Directory Structure
+
+This repository contains several Rust crates that implement the different building blocks of an Ethereum node. The high-level structure of the repository is as follows:
+
+- `crates/`
+    - [`db/`](crates/db): Strongly typed database bindings to [LibMDBX](https://github.com/vorot93/libmdbx-rs/) containing read/write access to Ethereum state and historical data (transactions, blocks etc.)
+    - [`executor/`](crates/executor): Blazing-fast instrumented EVM using [`revm`](https://github.com/bluealloy/revm/). Used during consensus, syncing & during transaction simulation / gas estimation.
+    - [`interfaces/`](crates/interfaces): Traits containing common abstractions across the components used in the system. For ease of unit testing, each crate importing the interface is recommended to create mock/in-memory implementations of each trait.
+    - `net/`
+        - [`p2p`](crates/net/p2p): Implements the Ethereum P2P protocol.
+        - [`rpc-api`](crates/net/rpc-api): Traits 
+            - Supported transports: HTTP, WS, IPC
+            - Supported namespaces: `eth_`, `engine_`, `debug_`
+        - [`rpc`](crates/net/rpc): Implementation of all ETH JSON RPC traits defined in `rpc-api`.
+        - [`rpc-types`](crates/net/rpc-types): Types relevant for the RPC endpoints above, grouped by namespace
+    - [`primitives/`](crates/stages): Commonly used types in Reth.
+    - [`stages/`](crates/stages): The staged sync pipeline, including implementations of each stage.
+    - [`transaction-pool/`](crates/transaction-pool): An in-memory pending transactions pool.
+- [`crate-template`](crate-template): Template crate to use when instantiating new crates under `crates/`.
+- [`bin/`](bin): Where all binaries are stored.
+- [`examples/`](examples): Example usage of the reth stack as a library.