Added a bunch more tests on the API 0.6. Fixed node/way/relation from_xml code to disallow duplicate tag keys.

app/controllers/node_controller.rb

@@ -71,9 +71,8 @@ class NodeController < ApplicationController
       else
         render :nothing => true, :status => :bad_request
       end
-    rescue OSM::APIVersionMismatchError => ex
-      render :text => "Version mismatch: Provided " + ex.provided.to_s +
-        ", server had: " + ex.latest.to_s, :status => :bad_request
+    rescue OSM::APIError => ex
+      render ex.render_opts
     rescue ActiveRecord::RecordNotFound
       render :nothing => true, :status => :not_found
     end