Added note about rotating transparent GIF images

Zebra_Image.php

@@ -1260,6 +1260,8 @@ public function resize($width = 0, $height = 0, $method = ZEBRA_IMAGE_CROP_CENTE
     /**
      *  Rotates the image given as {@link source_path} and outputs the resulted image as {@link target_path}.
      *
+     *  >   Note that rotating transparent GIFs will most likely **not** work!
+     *
      *  <code>
      *  // include the Zebra_Image library
      *  // (you don't need this if you installed using composer)

docs/Zebra_Image/Zebra_Image.html

@@ -743,7 +743,7 @@ <h4 id="methodrotate" class="method"><span><em>method</em></span> rotate()</h4>
 ) 
 </p>
 <p>Rotates the image given as <a href="../Zebra_Image/Zebra_Image.html#var$source_path">source_path</a> and outputs the resulted image as <a href="../Zebra_Image/Zebra_Image.html#var$target_path">target_path</a>.</p>
-<p><ol class="code"><li><div class="src-line"><span class="src-comm">//&nbsp;include&nbsp;the&nbsp;Zebra_Image&nbsp;library</span></div></li>
+<p><p class="highlight">Note that rotating transparent GIFs will most likely <strong>not</strong> work!</p><ol class="code"><li><div class="src-line"><span class="src-comm">//&nbsp;include&nbsp;the&nbsp;Zebra_Image&nbsp;library</span></div></li>
 <li><div class="src-line"><span class="src-comm">//&nbsp;(you&nbsp;don't&nbsp;need&nbsp;this&nbsp;if&nbsp;you&nbsp;installed&nbsp;using&nbsp;composer)</span></div></li>
 <li><div class="src-line">require&nbsp;<span class="src-str">'path/to/Zebra_Image.php'</span><span class="src-sym">;</span></div></li>
 <li><div class="src-line">&nbsp;</div></li>