Conflicts:
- README.md
  discarded upstream changes
- app/controllers/api/v1/bookmarks_controller.rb
  finally merged upstream, some code style fixes
  and slightly changed pagination code
- app/controllers/application_controller.rb
  changed upstream to always return HTML error pages
  slight conflict caused by theming code
- app/models/bookmark.rb
  finally merged upstream, no real conflict
- spec/controllers/api/v1/bookmarks_controller_spec.rb
  finally merged upstream, slightly changed pagination code