Remove redundant 'public' modifiers

CheckStyle reports 'public' being redundant on the constructor of
ApproveOption#Handler, but removing it causes test failures due to
org.kohsuke.args4j.Option requiring an explicitly public constructor.

Add a suppression for that one, and remove the 'public' in other
places where it's reported.

Change-Id: Ifbcf279ffa783d33b81efc1c675f468c3ea39135

gerrit-war/src/main/java/com/google/gerrit/httpd/UnzippedDistribution.java

@@ -36,7 +36,7 @@ class UnzippedDistribution implements PluginsDistribution {
   private ServletContext servletContext;
   private File pluginsDir;
 
-  public UnzippedDistribution(ServletContext servletContext) {
+  UnzippedDistribution(ServletContext servletContext) {
     this.servletContext = servletContext;
   }