Fix tutorial content related to navigation
Fix tutorial content related to navigation

This is a small update to make sure the tutorial flows smoothly. The current version is describing a step that is not needed and now incorrect. The paths were also updated from /app/... to /src/... to match new structure.
ionic-team/ionic-site,ionic-team/ionic-site,ionic-team/ionic-site,driftyco/ionic-site,driftyco/ionic-site,ionic-team/ionic-site,driftyco/ionic-site,driftyco/ionic-site,driftyco/ionic-site