Add README badges & update CI jobs to execute the CLI.

Author: thedodd

.github/workflows/ci.yaml

@@ -16,3 +16,8 @@ jobs:
       - uses: actions-rs/cargo@v1
         with:
           command: build
+      # verify that we can actually execute the CLI and get some output
+      - uses: actions-rs/cargo@v1
+        with:
+          command: run
+          args: -- -h

README.md

@@ -10,6 +10,12 @@
 </div>
 <br/>
 
+[![Build Status](https://github.com/thedodd/trunk/workflows/ci/badge.svg?branch=master)](https://github.com/thedodd/trunk/actions)
+[![Crates.io](https://img.shields.io/crates/v/trunk.svg)](https://crates.io/crates/trunk)
+[![License](https://img.shields.io/badge/license-MIT%2FApache--2.0-blue)](LICENSE)
+![Crates.io](https://img.shields.io/crates/d/trunk.svg)
+![Crates.io](https://img.shields.io/crates/dv/trunk.svg)
+
 Goals:
 - Leverage the wasm-bindgen ecosystem for all things related to building Rust WASM for the web.
 - Simple, zero-config bundling of WASM, JS loader & other assets (images, css, scss) via a source HTML file.