merge from master

app/assets/javascripts/application/accessibility.js

app/assets/javascripts/application/search.js

app/assets/stylesheets/application/search.scss

app/controllers/search_controller.rb

app/controllers/users_controller.rb

app/helpers/users_helper.rb

app/models/collection.rb

app/repositories/orient_db/collection_repository.rb

app/repositories/orient_db/learning_object_repository.rb

app/views/bookmarks/_bookmarks.html.erb

app/views/collections/show.html.erb

app/views/layouts/application.html.erb

app/views/search/_fetch.html.erb

app/views/search/index.html.erb

app/views/users/me.html.erb

lib/search_engine/orientdb_lucene.rb