Disable phpcs sniff for BC compat

In order to keep BC compatiblity, I had to introduce class_alias calls
in the True_ and False_ classes. This has a side-effect, which the phpcs
fails on.

Author: mvriel

phpcs.xml.dist

@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 <ruleset name="phpDocumentor">
- <description>The coding standard for phpDocumentor.</description>
+    <description>The coding standard for phpDocumentor.</description>
 
     <file>src</file>
     <file>tests/unit</file>
@@ -13,4 +13,9 @@
     <rule ref="SlevomatCodingStandard.Classes.SuperfluousAbstractClassNaming.SuperfluousPrefix">
         <exclude-pattern>*/src/*/Abstract*.php</exclude-pattern>
     </rule>
+
+    <rule ref="PSR1.Files.SideEffects.FoundWithSymbols">
+        <exclude-pattern>*/src/PseudoTypes/False_.php</exclude-pattern>
+        <exclude-pattern>*/src/PseudoTypes/True_.php</exclude-pattern>
+    </rule>
 </ruleset>