Example images for bulge question. Fixes #181.

app/lib/sloan_tree.coffee

@@ -24,10 +24,10 @@ SloanTree = new DecisionTree 'sloan', ->
 
   @question 'Bulge', 'How prominent is the central bulge, compared with the rest of the galaxy?', leadsTo: 'Is there anything odd?', ->
     @help "It's not always easy to tell, but look at the centre of the galaxy for a round bulge of stars which may obscure any bar and the spiral arms in this central region. Click to see larger images."
-    @answer 'No bulge', icon: 'bulge_none'
-    @answer 'Just noticeable', icon: 'bulge_noticeable'
-    @answer 'Obvious', icon: 'bulge_obvious'
-    @answer 'Dominant', icon: 'bulge_dominant'
+    @answer 'No bulge', icon: 'bulge_none', examples: 4
+    @answer 'Just noticeable', icon: 'bulge_noticeable', examples: 4
+    @answer 'Obvious', icon: 'bulge_obvious', examples: 4
+    @answer 'Dominant', icon: 'bulge_dominant', examples: 4
 
   @question 'Odd', 'Is there anything odd?', ->
     @help "We're looking for signs that the galaxy is merging, is disturbed, or has other unusual features. Click to see larger images."

css/common.styl

@@ -255,6 +255,22 @@ example-images()
   &.sloan-3_a-0_0    { background-position: -1200px  -900px }
   &.sloan-3_a-0_1    { background-position:  -400px -1400px }
   &.sloan-3_a-1_0    { background-position:  -500px  -600px }
+  &.sloan-4_a-0_0    { background: url(images/examples/sloan-4_a-0_0.jpg) center/cover }
+  &.sloan-4_a-0_1    { background: url(images/examples/sloan-4_a-0_1.jpg) center/cover }
+  &.sloan-4_a-0_2    { background: url(images/examples/sloan-4_a-0_2.jpg) center/cover }
+  &.sloan-4_a-0_3    { background: url(images/examples/sloan-4_a-0_3.jpg) center/cover }
+  &.sloan-4_a-1_0    { background: url(images/examples/sloan-4_a-1_0.jpg) center/cover }
+  &.sloan-4_a-1_1    { background: url(images/examples/sloan-4_a-1_1.jpg) center/cover }
+  &.sloan-4_a-1_2    { background: url(images/examples/sloan-4_a-1_2.jpg) center/cover }
+  &.sloan-4_a-1_3    { background: url(images/examples/sloan-4_a-1_3.jpg) center/cover }
+  &.sloan-4_a-2_0    { background: url(images/examples/sloan-4_a-2_0.jpg) center/cover }
+  &.sloan-4_a-2_1    { background: url(images/examples/sloan-4_a-2_1.jpg) center/cover }
+  &.sloan-4_a-2_2    { background: url(images/examples/sloan-4_a-2_2.jpg) center/cover }
+  &.sloan-4_a-2_3    { background: url(images/examples/sloan-4_a-2_3.jpg) center/cover }
+  &.sloan-4_a-3_0    { background: url(images/examples/sloan-4_a-3_0.jpg) center/cover }
+  &.sloan-4_a-3_1    { background: url(images/examples/sloan-4_a-3_1.jpg) center/cover }
+  &.sloan-4_a-3_2    { background: url(images/examples/sloan-4_a-3_2.jpg) center/cover }
+  &.sloan-4_a-3_3    { background: url(images/examples/sloan-4_a-3_3.jpg) center/cover }
   &.sloan-6_x-0_0    { background-position: -1200px  -600px }
   &.sloan-6_x-0_1    { background-position:  -100px  -500px }
   &.sloan-6_x-1_0    { background-position:  -300px  -200px }