Update codequality/checkstyle.xml

Removing as it appears to no longer be available in the latest version of checkstyle that comes with gradle 1.4

Author: Greg Orzell

codequality/checkstyle.xml

@@ -128,7 +128,6 @@
         <!-- Checks for common coding problems               -->
         <!-- See http://checkstyle.sf.net/config_coding.html -->
         <!-- <module name="AvoidInlineConditionals"/> -->
-        <module name="DoubleCheckedLocking"/>    <!-- MY FAVOURITE -->
         <module name="EmptyStatement"/>
         <module name="EqualsHashCode"/>
         <module name="HiddenField">