Type of parameter 'classid' changed in fetch keyword function

*Title: Type of parameter 'classid' changed in fetch keyword function

*Documentation:
Fetch keyword function has one parameter 'classid', which can only be integer before 3.6.
Now it can be either a single class id or an array of class id.

*Example:
The following example will explain how to use keyword fetch function:

<code>
{let kword_list=fetch( 'content', 'keyword',
                       hash( alphabet, $alphabet,
                             limit, 10,
                             offset, $view_parameters.offset,
                             classid, array( 26, 32 ) ) )}
code
{/let}
</code>