[ZPT] extended path notation

[ethan mindlace fremen]

I'm doing a fair amount of PT lately. In my main_template, I have 
probably 60 or so image references. Some of these are "stand alone" 
images, and some of them are in background tags. Some are also links.

So I have to do this:

<td background="dark_grey_bg.png" tal:attributes="background 
here/dark_grey_bg.png/absolute_url">

and:

<img src="button.png" tal:replace="structure 
python:('here/button.png').tag(border='0')">

mostly, i think the fault lies with the image object, but I have two 
suggestions:

1. allow objects to suggest the attr's they'd like to provide.

<img src="logo.png" border="0" tal:attributes="here/logo.png/attrs">

would replace the src attr and add width and height attrs, but leave 
"border" alone.

2. extend path notation to include variables:

<img src="logo.png" tal:replace="structure here/logo.png?border=0">

both could be handy, but the latter might be more used in non-image 
contexts.
~ethan