This is a small patch which adds a "permission" keyword to 
HTMLRequest.batch. 

This allows templates to use batch() to filter based on other permissions 
besides "View". I had need of this in my own tracker since I wanted to 
render a list of issues based on a separate "Search" permission, instead 
of whether they had "View" permission for the issue.  

The default value is identical to the current behavior, so this patch 
should not affect anyone who doesn't make use of the keyword.