fix(ZP-645): PHP 5.4+ ob_start() needs an extra flag to allow

truncate.

We need to set flags before calling ob_end_flush, ob_clean...
Signed-off-by: Francisco Miguel Biete &lt;fbiete@gmail.com&gt; <fmbiete@gmail.com>

src/index.php

@@ -43,7 +43,13 @@
 * Consult LICENSE file for details
 ************************************************/
 
-ob_start(null, 1048576);
+
+if (version_compare(phpversion(), '5.4.0') < 0) {
+    ob_start(null, 1048576);
+}
+else {
+    ob_start(null, 1048576, PHP_OUTPUT_HANDLER_STDFLAGS);
+}
 
 // ignore user abortions because this can lead to weird errors - see ZP-239
 ignore_user_abort(true);