Add common configuration logic for "input file templates"

just used in one batch so far but should be useful for many more..once
can get around to migrating them

had to rework the configuration logic to use HTML form instead of
JSON, to allow for the file uploads

tailbone/templates/master/index.mako

@@ -165,6 +165,11 @@
   % if master.configurable and master.has_perm('configure'):
       <li>${h.link_to("Configure {}".format(config_title), url('{}.configure'.format(route_prefix)))}</li>
   % endif
+  % if master.has_input_file_templates and master.has_perm('download_template'):
+      % for template in six.itervalues(input_file_templates):
+          <li>${h.link_to("Download {} Template".format(template['label']), template['effective_url'])}</li>
+      % endfor
+  % endif
 </%def>
 
 <%def name="grid_tools()">