Add test for negative 0

Author: Girgias

Zend/tests/float_to_int/negative_zero_check.phpt

@@ -0,0 +1,15 @@
+--TEST--
+Negative 0 check
+--FILE--
+<?php
+
+$negativeZero = -0.0;
+var_dump($negativeZero);
+var_dump($negativeZero === (float)(int)$negativeZero);
+var_dump($negativeZero === 0.0);
+
+?>
+--EXPECT--
+float(-0)
+bool(true)
+bool(true)