feat(readme): update desc to make it clearer that publishing is optional

README.md

@@ -7,9 +7,10 @@
 
 This tool seeks to be a one-stop shop for building and working with rust-
 generated WebAssembly that you would like to interop with JavaScript, in the
-browser or with Node.js. `wasm-pack` helps you build and publish rust-generated
-WebAssembly to the npm registry to be used alongside any other javascript
-package in workflows that you already use, such as [webpack] or [greenkeeper].
+browser or with Node.js. `wasm-pack` helps you build rust-generated
+WebAssembly packages that you could publish to the npm registry, or otherwise use
+alongside any javascript packages in workflows that you already use, such as [webpack]
+or [greenkeeper].
 
 [bundler-support]: https://github.com/rustwasm/team/blob/master/goals/bundler-integration.md#details
 [webpack]: https://webpack.js.org/