arti-client example: Try to make the comments a little more clear.

I'm not 100% sure this is better, but it might help the user
understand how Arti works a bit better.

crates/arti-client/src/lib.rs

@@ -55,14 +55,16 @@
 //! # use tokio_crate as tokio;
 //! # #[tokio::main]
 //! # async fn main() -> Result<()> {
-//! // The client config includes things like where to store persistent Tor network state.
+//! // The client configuration describes how to connect to the Tor network,
+//! // and what directories to use for storing persistent state.
 //! let config = TorClientConfig::sane_defaults()?;
-//! // Arti needs a handle to an async runtime in order to spawn async tasks.
-//! // (See "Multiple runtime support" below.)
+//! // Arti needs a handle to an async runtime in order to spawn tasks and use the
+//! // network. (See "Multiple runtime support" below.)
 //! let rt = tor_rtcompat::tokio::current_runtime()?;
 //!
 //! // Start the Arti client, and let it bootstrap a connection to the Tor network.
-//! // (This takes a while to gather the necessary consensus state, etc.)
+//! // (This takes a while to gather the necessary directory information.
+//! // It uses cached information when possible.)
 //! let tor_client = TorClient::bootstrap(rt, config).await?;
 //!
 //! // Initiate a connection over Tor to example.com, port 80.
@@ -76,8 +78,7 @@
 //!     .await?;
 //!
 //! // IMPORTANT: Make sure the request was written.
-//! // Arti buffers data by default due to the design of the Tor protocol, so flushing the
-//! // buffer is usually required.
+//! // Arti buffers data, so flushing the buffer is usually required.
 //! stream.flush().await?;
 //!
 //! // Read and print the result.
@@ -133,6 +134,9 @@
 //!
 //! `async-std` -- Build with support for the `async_std` backend.
 //!
+//! `static` -- Link with static versions of your system dependencies,
+//! including sqlite and/or openssl.
+//!
 //! `experimental-api` -- Build with experimental, unstable API support.
 //! Note that these APIs are NOT covered by semantic versioning guarantees:
 //! we might break them or remove them between patch versions.