Declare empty package dirs as output dirs

Otherwise newer versions of Gradle will see the outputs as stale and
remove the directory between having created the directory and copying
files into the directory (leading to the directory being created again,
this time missing some sub-directories).

Author: jasontedor

distribution/build.gradle

@@ -324,12 +324,14 @@ configure(distributions.findAll { ['deb', 'rpm'].contains(it.name) }) {
   task createEtc(type: EmptyDirTask) {
     dir "${packagingFiles}/etc/elasticsearch"
     dirMode 0750
+    outputs.dir dir
   }
 
   task createEtcScripts(type: EmptyDirTask) {
     dependsOn createEtc
     dir "${packagingFiles}/etc/elasticsearch/scripts"
     dirMode 0750
+    outputs.dir dir
   }
 
   task fillEtc(type: Copy) {