- add truecolortopallete and istruecolor test

- titles for colorclosest/resolve...

ext/gd/tests/colorclosest.phpt

@@ -2,7 +2,7 @@
 imageclosest
 --SKIPIF--
 <?php
-        if (!function_exists('imageclosest')) die("skip gd extension not available\n");
+        if (!function_exists('imagecolorclosest')) die("skip gd extension not available\n");
 ?>
 --FILE--
 <?php

ext/gd/tests/colorresolve.phpt

@@ -2,7 +2,7 @@
 imagecolorresolve
 --SKIPIF--
 <?php
-        if (!function_exists('imageresolve')) die("skip gd extension not available\n");
+        if (!function_exists('imagecolorresolve')) die("skip gd extension not available\n");
 ?>
 --FILE--
 <?php

ext/gd/tests/truecolor.phpt

@@ -0,0 +1,19 @@
+--TEST--
+imageistruecolor, truecolortopalette
+--SKIPIF--
+<?php
+        if (!function_exists('imagetruecolortopalette')) die("skip gd extension not available\n");
+?>
+--FILE--
+<?php
+$im = imagecreatetruecolor(1,1); 
+if (imageistruecolor($im)) echo "ok\n";
+
+if (imagetruecolortopalette($im, 1,2)) echo "ok\n";
+if (!imageistruecolor($im)) echo "ok\n";
+
+?>
+--EXPECTF--
+ok
+ok
+ok