refactor(README.md): add instructions for Yarn

README.md

@@ -32,8 +32,21 @@
 - **This repo will not run locally if you do not also have the LBRY app/daemon and the [web-daemon](https://github.com/lbryio/web-daemon) running.**
 - When running locally and completing the tipping example in Playground, the LBC donated to a creator comes from _your_ LBC balance. Otherwise, the example will fail. On production, the donated LBC comes from LBRY.
 
-## Installation
-`npm i`
+## Local Installation
+
+### Npm
+```bash
+npm install
+```
+
+### Alternatively Yarn
+
+There is a yarn.lock file, you can thus use yarn to install a guaranteed working configuration of packages. This is generally a lot faster to install and more stable. Yarn as a cli is however not necessarily more stable than npm and as such it's optional. Install yarn here: https://yarnpkg.com/en/docs/install
+
+Then 
+```bash
+yarn install
+```
 
 ## Development
 `npm run watch` and visit [localhost:8080](http://localhost:8080)