Add channel as a product type.

Currently I'm using a (not very well) downscaled version of the NixOS
logo, so we want to replace it by a proper image ASAP.

Other than that, the idea is to have something like this in
hydra-build-products:

file channel $out/channel.tar.bz2

Right now of course, it's only displayed at the corresponding builds, so
we might want to have aggregates on all channels for a project, jobset
or maybe even single jobs?

Signed-off-by: aszlig <aszlig@redmoonstudios.org>

src/root/product-list.tt

@@ -136,6 +136,8 @@
             <img src="[% c.uri_for("/static/images/iso.png") %]" alt="ISO" /> ISO-9660 CD/DVD image <tt>[% product.name %]</tt>
           [% CASE "binary-dist" %]
             <img src="[% c.uri_for("/static/images/binary-dist.png") %]" alt="Binary distribution" /> Binary distribution <tt>[% product.name %]</tt>
+          [% CASE "channel" %]
+            <img src="[% c.uri_for("/static/images/channel.png") %]" alt="Channel" /> Channel expressions <tt>[% product.name %]</tt>
           [% CASE DEFAULT %]
             File <tt>[% product.name %]</tt> of type <tt>[% product.subtype %]</tt>
           [% END %]