PHPCS ruleset: make the file level @author tag optional

Related to 155 and 663

Author: jrfnl

phpcs.xml.dist

@@ -23,6 +23,7 @@
         <exclude name="PEAR.NamingConventions.ValidFunctionName"/>
         <exclude name="PEAR.NamingConventions.ValidVariableName"/>
         <exclude name="PEAR.Commenting.ClassComment"/>
+        <exclude name="PEAR.Commenting.FileComment.MissingAuthorTag"/>
         <exclude name="PEAR.Commenting.FileComment.MissingCategoryTag"/>
         <exclude name="PEAR.Commenting.FileComment.MissingPackageTag"/>
         <exclude name="PEAR.Commenting.FileComment.MissingLinkTag"/>