v2017-07-13.0

• Hide beta section types
• update Code.org's blog from Tumblr to Medium
• DTS (Levelbuilder > Staging)
• Fix validation failures and error page display
• Courses: show extra content for students in en
• Exit build step with the same status as rake build
• Progress Bubbles Cleanup
• Add filters and paging to the workshop materials admin list
• Add /p/artist_k1 and /p/playlab_k1 project pages
• Call API to import a Google Classroom on "Import Section" click
• migrate sections to have courses assigned
• Student home: if cookie, link to /home for sign-in/header/hamburger
• Student home: pass required base URL parameter to Sections
• Student homepage: include legacy section management UI
• AppLab setProperty() bug fix
• Student home: only show one way to find a new course
• Courses: update UI for course catalog & hoc options
• Student homepage: only one UI tip should show
• Remove isPathForward from 'harvester_untilAtCrop'
• Google Classroom section inheritance
• Courses: expanded list of recent courses needs spacers
• redirect to course page on login if section has course and no script
• cleanup unused valid_courses
• Forward Slack CloudWatch Events to environment-specific channel
• Add background field to playlab level editor
• Add disable_procedure_autopopulate option to Blockly levels
• DTL (Test > Levelbuilder: 8f8fa160)
• auto-commit new video thumbnails generated in bin/cron/fetch_external_resources