Add a README

... with the most basic information about the coding standard.

Author: jrfnl

README.md

@@ -0,0 +1,29 @@
+PHP Code Style
+=================
+
+Basic, PSR-12 based, coding standard for use by projects in the PHP Parallel Lint GitHub organisation.
+
+## Installation
+
+Install this standard via Composer:
+
+```bash
+composer require --dev php-parallel-lint/php-code-style
+```
+
+## Using the standard
+
+Once installed for a project, use this standard via the command-line:
+```bash
+vendor/bin/phpcs . --standard=PHPParallelLint
+```
+
+Or use the standard in a project specific PHPCS ruleset:
+```xml
+<?xml version="1.0"?>
+<ruleset name="Project Name">
+
+    <rule ref="PHPParallelLint"/>
+
+</ruleset>
+```