Revert "Merge pull request #67 in ZP/z-push from...

Revert "Merge pull request #67 in ZP/z-push from bugfix/ZP-726-infinit-loop-if-non-stream-given-for-an-attachment to develop"

This reverts commit 16800140.

src/lib/request/getattachment.php

@@ -61,8 +61,7 @@ class GetAttachment extends RequestProcessor {
             $stream = $attachment->data;
             ZLog::Write(LOGLEVEL_DEBUG, sprintf("HandleGetAttachment(): attachment stream from backend: %s", $stream));
 
-            // need to check for a resource here, as eg. feof('Error') === false and causing infinit loop in while!
-            if (!is_resource($stream))
+            if ($stream == null)
                 throw new StatusException(sprintf("HandleGetAttachment(): No stream resource returned by backend for attachment: %s", $attname), SYNC_ITEMOPERATIONSSTATUS_INVALIDATT);
 
             header("Content-Type: application/octet-stream");