added cve tag to xml file

spec/lib/common/models/vulnerability/output_spec.rb

@@ -19,7 +19,13 @@ describe Vulnerability::Output do
       @module   = 'gathering/yolo'
       @expected = modules_url + @module
     end
-  end
+    end
+
+    describe '::cve_url' do
+        it 'returns the correct url' do
+            Vulnerability::Output.cve_url('1111-1111').should == 'http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-1111-1111'
+        end
+    end
 
   describe '#output' do
     # How to test it ? oO