Merge branch 'develop' into fix_php7_issues

Author: troosan

src/PhpWord/Writer/Word2007/Style/Frame.php

@@ -28,6 +28,8 @@
  */
 class Frame extends AbstractStyle
 {
+    const PHP_32BIT_INT_MAX = 2147483647;
+
     /**
      * Write style.
      */
@@ -39,7 +41,8 @@ public function write()
         }
         $xmlWriter = $this->getXmlWriter();
 
-        $zIndices = array(FrameStyle::WRAP_INFRONT => PHP_INT_MAX, FrameStyle::WRAP_BEHIND => -PHP_INT_MAX);
+        $maxZIndex = min(PHP_INT_MAX, self::PHP_32BIT_INT_MAX);
+        $zIndices = array(FrameStyle::WRAP_INFRONT => $maxZIndex, FrameStyle::WRAP_BEHIND => -$maxZIndex);
 
         $properties = array(
             'width'     => 'width',