Blueprint should remove <title> tag from app/index.html if ember-page-title is present

[raido]

Due to constraints on DOM access in Fastboot context, we need to make sure that upon installing ember-cli-fastboot and ember-page-title is present, we remove title element from app/index.html

Main issue on ember-page-title side - ember-cli/ember-page-title#174

Same change will be done for ember-page-title blueprint.