Impl(Task/Ext/Archive/ZipTask): savefileattributes flag

By default false when omitted, file permissions attribute are not saved.
When setting the savefileattributes to true, files permissions
are savec as external attributes in the Zip archive.

Example:

```xml
<zip includeemptydirs="true" destfile="${project.basedir}/test.zip" basedir="./dir" savefileattributes="true">
    <fileset dir="dir">
        <include name="**/**"/>
    </fileset>
</zip>
```

src/Phing/Task/Ext/Archive/ZipTask.php

@@ -59,6 +59,8 @@ class ZipTask extends MatchingTask
 
     private $ignoreLinks = false;
 
+    private $saveFileAttributes = false;
+
     /**
      * File path prefix in zip archive
      *
@@ -73,6 +75,38 @@ class ZipTask extends MatchingTask
      */
     private $comment = '';
 
+    /**
+     * Propagates the directory's mTime and permissions in the Zip archive if supported.
+     *
+     * @param \ZipArchive $zip       The Zip archive
+     * @param File        $f         The File handle to the directory
+     * @param string      $pathInZip The path of the directory in the Zip archive
+     *
+     * @throws IOException
+     */
+    private static function fixDirAttributes($zip, $f, $pathInZip)
+    {
+        $indexInZip = $zip->locateName('/' === mb_substr($pathInZip, -1) ? $pathInZip : $pathInZip . '/');
+        if (false !== $indexInZip) {
+            $zip->setMtimeIndex($indexInZip, $f->lastModified());
+            $filePerms = fileperms($f->getPath());
+            if (false !== $filePerms) { // filePerms supported
+                $zip->setExternalAttributesIndex($indexInZip, \ZipArchive::OPSYS_DEFAULT, $filePerms << 16);
+            }
+        }
+    }
+    /**
+     * Removes all external attributes from the Zip archive.
+     *
+     * @param \ZipArchive $zip The Zip archive
+     */
+    private static function clearExternalAttributes($zip)
+    {
+        for ($i = 0, $count = $zip->count(); $i < $count; ++$i) {
+            $zip->setExternalAttributesIndex($i, \ZipArchive::OPSYS_DOS, null);
+        }
+    }
+
     /**
      * Add a new fileset.
      *
@@ -150,6 +184,17 @@ public function setIgnoreLinks($bool)
         $this->ignoreLinks = (bool) $bool;
     }
 
+    /**
+     * Set the save file attributes flag.
+     *
+     * @param  bool $bool Flag if file attributes should be saved
+     * @return void
+     */
+    public function setSaveFileAttributes($bool)
+    {
+        $this->saveFileAttributes = (bool) $bool;
+    }
+
     /**
      * Add a comment to the zip archive.
      *
@@ -236,6 +281,10 @@ public function main()
 
             $this->addFilesetsToArchive($zip);
 
+            if (!$this->saveFileAttributes) {
+                self::clearExternalAttributes($zip);
+            }
+
             $zip->close();
         } catch (IOException $ioe) {
             $msg = "Problem creating ZIP: " . $ioe->getMessage();
@@ -306,12 +355,7 @@ private function addFilesetsToArchive($zip)
                 if ($f->isDirectory()) {
                     if ($pathInZip != '.') {
                         $zip->addEmptyDir($pathInZip);
-                        $filePerms = fileperms($f->getPath());
-                        if (false !== $filePerms) { // filePerms supported
-                            $dirAttrs = $filePerms << 16;
-                            $dirAttrName = $pathInZip . '/';
-                            $zip->setExternalAttributesName($dirAttrName, \ZipArchive::OPSYS_UNIX, $dirAttrs);
-                        }
+                        static::fixDirAttributes($zip, $f, $pathInZip);
                     }
                 } else {
                     $zip->addFile($f->getAbsolutePath(), $pathInZip);