remove checkstyle ExplicitInitialization check

"Variable explicitly initialized to 'false' (default value for its type)"

I never remember what the default init value of booleans are, so this error
is quite annoying to me, and I can't see the harm of this behavior.
checkstyle says: "So in this case, x gets initialized to 0 twice, and bar
gets initialized to null twice. So there is a minor inefficiency."

config/checkstyle/checkstyle.xml

@@ -81,7 +81,6 @@
         <module name="WhitespaceAfter" />
         <module name="WhitespaceAround" />
         <module name="UnnecessaryParentheses" />
-        <module name="ExplicitInitialization" />
 
         <module name="ModifierOrder" />
         <module name="RedundantModifier" />