Show Google Code image attachments inline.

lib/gitlab/google_code_import/importer.rb

@@ -314,8 +314,12 @@ module Gitlab
         raw_attachments.map do |attachment|
           next if attachment["isDeleted"]
 
-          link = "https://storage.googleapis.com/google-code-attachments/#{@repo.name}/issue-#{issue_id}/comment-#{comment_id}/#{attachment["fileName"]}"
-          "[#{attachment["fileName"]}](#{link})"
+          filename = attachment["fileName"]
+          link = "https://storage.googleapis.com/google-code-attachments/#{@repo.name}/issue-#{issue_id}/comment-#{comment_id}/#{filename}"
+          
+          text = "[#{filename}](#{link})"
+          text = "!#{text}" if filename =~ /\.(png|jpg|jpeg|gif|bmp|tiff)\z/
+          text
         end.compact
       end
     end

spec/fixtures/GoogleCodeProjectHosting.json

@@ -372,6 +372,11 @@
               "fileName" : "tint2_task_scrolling.diff",
               "fileSize" : 3059,
               "mimetype" : "text/x-c++; charset=us-ascii"
+            }, {
+              "attachmentId" : "000",
+              "fileName" : "screenshot.png",
+              "fileSize" : 0,
+              "mimetype" : "image/png"
             } ]
           }, {
             "id" : 1,

spec/lib/gitlab/google_code_import/importer_spec.rb

@@ -49,7 +49,8 @@ describe Gitlab::GoogleCodeImport::Importer do
       expect(issue.description).to include('Patch is attached that adds two new mouse\-actions \(next\_taskprev\_task\)')
       expect(issue.description).to include('that can be used for exactly that purpose.')
       expect(issue.description).to include('all the best!')
-      expect(issue.description).to include('https://storage.googleapis.com/google-code-attachments/tint2/issue-169/comment-0/tint2_task_scrolling.diff')
+      expect(issue.description).to include('[tint2_task_scrolling.diff](https://storage.googleapis.com/google-code-attachments/tint2/issue-169/comment-0/tint2_task_scrolling.diff)')
+      expect(issue.description).to include('![screenshot.png](https://storage.googleapis.com/google-code-attachments/tint2/issue-169/comment-0/screenshot.png)')
     end
 
     it "imports issue comments" do