intval: changed example from 4.2 to 4.7 (#4566)

This is to emphasize intval truncates it back to 4, and there's another function for rounding

Author: anttiryt

reference/var/functions/intval.xml

@@ -132,7 +132,7 @@
 <![CDATA[
 <?php
 echo intval(42);                      // 42
-echo intval(4.2);                     // 4
+echo intval(4.7);                     // 4
 echo intval('42');                    // 42
 echo intval('+42');                   // 42
 echo intval('-42');                   // -42