fix lang.hitch bug and add map loaded function
fix lang.hitch bug and add map loaded function

Esri/application-boilerplate-js,brudo/application-boilerplate-js,brudo/application-boilerplate-js,Ricardh522/application-boilerplate-js,shekhawatravi/application-boilerplate-js,Esri/application-boilerplate-js,Ricardh522/application-boilerplate-js,shekhawatravi/application-boilerplate-js