Ruleset: various tweaks for PHP-Code-Style 2.0

* Scan all PHP files, not just the file in `src` for improved consistency across the code base, but exclude the `vendor` and the `build` (code coverage) directories.
* Enable parallel scanning for faster results.
* Use the ruleset from PHP-Code-Style by name.
* Set the `testVersion` for use with PHPCompatibility.
* Include minimal documentation in the ruleset.

phpcs.xml.dist

@@ -1,8 +1,20 @@
 <?xml version="1.0"?>
-<ruleset name="Jakub Onderka Coding Standard">
+<ruleset name="PHP-Console-Color">
     <description>A coding standard for Jakub Onderka's projects.</description>
 
-    <file>./src/</file>
+    <!--
+    #############################################################################
+    COMMAND LINE ARGUMENTS
+    https://github.com/squizlabs/PHP_CodeSniffer/wiki/Annotated-ruleset.xml
+    #############################################################################
+    -->
+
+    <!-- Scan all files. -->
+    <file>.</file>
+
+    <!-- Exclude dependencies and auto-generated files. -->
+    <exclude-pattern>*/build/*</exclude-pattern>
+    <exclude-pattern>*/vendor/*</exclude-pattern>
 
     <!-- Only check PHP files. -->
     <arg name="extensions" value="php"/>
@@ -13,6 +25,19 @@
     <!-- Strip the filepaths down to the relevant bit. -->
     <arg name="basepath" value="./"/>
 
-    <rule ref="./vendor/php-parallel-lint/php-code-style/ruleset.xml"/>
+    <!-- Check up to 8 files simultaneously. -->
+    <arg name="parallel" value="8"/>
+
+
+    <!--
+    #############################################################################
+    USE THE PHPParallelLint RULESET
+    #############################################################################
+    -->
+
+    <!-- Set the supported PHP versions for PHPCompatibility (included in PHPParallelLint). -->
+    <config name="testVersion" value="5.3-"/>
+
+    <rule ref="PHPParallelLint"/>
 
 </ruleset>