chore(docs): Update tonic-build docs (#22)

tonic-build/src/lib.rs

@@ -1,6 +1,23 @@
 //! `tonic-build` compiles `proto` files via `prost` and generates service stubs
 //! and proto definitiones for use with `tonic`.
 //!
+//! # Features
+//!
+//! `tonic-build` only comes with one `rustfmt` feature which enables the usage of
+//! the `rustfmt` binary to format the generated code. This is enabled by default.
+//!
+//! # Required dependencies
+//!
+//! ```toml
+//! [dependencies]
+//! bytes = <bytes-version>
+//! tonic = <tonic-version>
+//! prost = <prost-version>
+//!
+//! [build-dependencies]
+//! tonic-build = <tonic-version>
+//! ```
+//!
 //! # Examples
 //! Simple
 //!

tonic-examples/Cargo.toml

@@ -48,7 +48,6 @@ path = "src/tls/server.rs"
 tonic = { path = "../tonic", features = ["rustls"] }
 bytes = "0.4"
 prost = "0.5"
-prost-derive = "0.5"
 
 tokio = "=0.2.0-alpha.6"
 futures-preview = { version = "=0.3.0-alpha.19", default-features = false, features = ["alloc"]}