document raw() arguments as a buffer in guide

website/guide/duktapebuiltins.html

@@ -586,7 +586,7 @@ converted to tail calls, so this is not a practical issue.
 </tr>
 </thead>
 <tbody>
-<tr><td class="propname">raw</td><td>Output a formatted log line, by default writes to <code>stderr</code>.</td></tr>
+<tr><td class="propname">raw</td><td>Output a formatted log line (buffer value), by default writes to <code>stderr</code>.</td></tr>
 <tr><td class="propname">fmt</td><td>Format a single (object) argument.</td></tr>
 <tr><td class="propname">trace</td><td>Write a trace level (level 0, TRC) log entry.</td></tr>
 <tr><td class="propname">debug</td><td>Write a debug level (level 1, DBG) log entry.</td></tr>