Refactor/rename refresh all DNS action

I'm moving it out of the scrap folder too because there's nothing else
in there and we do want to retain this indefinitely because it's a useful
tool for performing DNS writer migrations.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160168902

java/google/registry/env/common/tools/WEB-INF/web.xml

@@ -113,7 +113,7 @@
   <!-- Refreshes all active domains in DNS -->
   <servlet-mapping>
     <servlet-name>tools-servlet</servlet-name>
-    <url-pattern>/_dr/task/refreshAllDomains</url-pattern>
+    <url-pattern>/_dr/task/refreshDnsForAllDomains</url-pattern>
   </servlet-mapping>
 
   <!-- Registrar detail report publishing action. -->