Add overlay badge support

Support so print can print only important text.

SVG modified to use display:inline/none based on overlay True/False and
a symlink to make it easy to change to a completely seperate svg if that
is not optimal.

SVG added layers to split text and graphic so graphics can be easily
hidden and printed.

Closes: #38

pinaxcon/templates/registrasion/badge_overlay.svg

@@ -0,0 +1 @@
+badge.svg

vendor/registrasion/registrasion/views.py

@@ -1146,8 +1146,8 @@ def _convert_img(img, outformat="png",dpi=200,width=None):
                          stdout=subprocess.PIPE).stdout
     return out
 
-def render_badge(user, format="png"):
-    rendered = render_badge_svg(user)
+def render_badge(user, format="png", overlay=False):
+    rendered = render_badge_svg(user, overlay=overlay)
     if format == "png":
         rendered = _convert_img(rendered, outformat="png")
     elif format == "pdf":
@@ -1167,14 +1167,20 @@ def render_badge(user, format="png"):
 
     return response
 
-def render_badge_svg(user):
+def render_badge_svg(user, overlay=False):
     ''' Renders a single user's badge as SVG. '''
 
     data = {
         "user": user,
+        "overlay": overlay
     }
 
-    t = loader.get_template('registrasion/badge.svg')
+    if overlay:
+        template = 'registrasion/badge_overlay.svg'
+    else:
+        template = 'registrasion/badge.svg'
+
+    t = loader.get_template(template)
     return t.render(data)
 
 def badges(request):