added CORS information to tracks guide. Fixes videojs#837

docs/guides/tracks.md

@@ -32,6 +32,11 @@ Once you have your WebVTT file created, you can add it to Video.js using the tra
 </video>
 ```
 
+Subtitles from Another Domain
+-----------------------------
+Because we're pulling in the text track file via Javascript, the [same-origin policy](http://en.wikipedia.org/wiki/Same_origin_policy) applies. If you'd like to have a player served from one domain,
+but the text track served from another, you'll need to [enable CORS](http://enable-cors.org/) in order to do so.
+
 Track Attributes
 ----------------
 Additional settings for track tags.
@@ -92,10 +97,10 @@ The two-letter code (valid BCP 47 language tag) for the language of the text tra
         <tr><th>fj<th><td>Fiji</td></tr>
         <tr><th>fi<th><td>Finnish</td></tr>
       </table>
-      
+
     </td>
     <td>
-      
+
       <table>
         <tr><th>fr<th><td>French</td></tr>
         <tr><th>fy<th><td>Frisian</td></tr>
@@ -135,10 +140,10 @@ The two-letter code (valid BCP 47 language tag) for the language of the text tra
         <tr><th>lo<th><td>Laothian</td></tr>
         <tr><th>la<th><td>Latin</td></tr>
       </table>
-      
+
     </td>
     <td>
-      
+
       <table>
         <tr><th>lv<th><td>Latvian (Lettish)</td></tr>
         <tr><th>li<th><td>Limburgish ( Limburger)</td></tr>
@@ -178,10 +183,10 @@ The two-letter code (valid BCP 47 language tag) for the language of the text tra
         <tr><th>ii<th><td>Sichuan Yi</td></tr>
         <tr><th>sd<th><td>Sindhi</td></tr>
       </table>
-      
+
     </td>
     <td>
-      
+
       <table>
         <tr><th>si<th><td>Sinhalese</td></tr>
         <tr><th>ss<th><td>Siswati</td></tr>
@@ -219,7 +224,7 @@ The two-letter code (valid BCP 47 language tag) for the language of the text tra
         <tr><th>yo<th><td>Yoruba</td></tr>
         <tr><th>zu<th><td>Zulu</td></tr>
       </table>
-      
+
     </td>
   </tr>
 </table>