Trivial: Reformat README.md.

Change-Id: Id6774593628a2091dda8b529b0cfba31d5e6a985

README.md

diff --git a/README.md b/README.md
index f7143d3..9f64b1b 100644
--- a/README.md
+++ b/README.md
@@ -1,20 +1,29 @@
 # Linux Tests
-This repository contains utilities for running integration tests for Linux guests under Machina.
+
+This repository contains utilities for running integration tests for Linux
+guests under Machina.
 
 ## Build
-First install rust (follow the instructions of the rustup tool):
-```
+
+First install rust (follow the instructions of the `rustup` tool):
+
+```sh
 $ curl https://sh.rustup.rs -sSf | sh
 $ source ~/.cargo/env
 ```
 
-Next we add some new targets for cross-compiling and static linking. Rust supports statically linking libc by replacing the usual gnu libc with musl (see [The Rust Book: Advanced Linking](https://doc.rust-lang.org/1.9.0/book/advanced-linking.html)).
-```
+Next we add some new targets for cross-compiling and static linking. Rust
+supports statically linking libc by replacing the usual GNU libc with musl (see
+[The Rust Book: Advanced Linking](https://doc.rust-lang.org/1.9.0/book/advanced-linking.html)).
+
+```sh
 $ rustup target add x86_64-unknown-linux-musl
 $ rustup target add aarch64-unknown-linux-musl
 ```
 
-Lastly, run the build script for your desired architecture. This will invoke cargo for you as well as create an ext2 image in out/.
-```
+Lastly, run the build script for your desired architecture. This will invoke
+cargo for you as well as create an ext2 image in `out/`.
+
+```sh
 $ ./build.sh {arm64|x64}
 ```