Add SpaceAfterNot rule (#29)

Author: Dumoulin

phpcs/ruleset.xml

@@ -27,6 +27,7 @@
         </properties>
     </rule>
     <rule ref="Generic.Formatting.SpaceAfterCast"/>
+    <rule ref="Generic.Formatting.SpaceAfterNot"/>
     <rule ref="Generic.Functions.CallTimePassByReference"/>
     <rule ref="Generic.Functions.FunctionCallArgumentSpacing"/>
     <rule ref="Generic.Functions.OpeningFunctionBraceBsdAllman"/>