Added support for multilingual search

Gulpfile.babel.js

lib/declarations/lunr.js

lib/tasks/assets/javascripts/build/languages.js

material/assets/javascripts/application-71e40776cb.js

material/assets/javascripts/lunr/lunr.da.js

material/assets/javascripts/lunr/lunr.de.js

material/assets/javascripts/lunr/lunr.du.js

material/assets/javascripts/lunr/lunr.es.js

material/assets/javascripts/lunr/lunr.fi.js

material/assets/javascripts/lunr/lunr.fr.js

material/assets/javascripts/lunr/lunr.hu.js

material/assets/javascripts/lunr/lunr.it.js

material/assets/javascripts/lunr/lunr.jp.js

material/assets/javascripts/lunr/lunr.multi.js

material/assets/javascripts/lunr/lunr.no.js

material/assets/javascripts/lunr/lunr.pt.js

material/assets/javascripts/lunr/lunr.ro.js

material/assets/javascripts/lunr/lunr.ru.js

material/assets/javascripts/lunr/lunr.stemmer.support.js

material/assets/javascripts/lunr/lunr.sv.js