[fix bug 986052] Add documentation for running Mozilla.UITour on Bedrock
Merge pull request #1814 from alexgibson/bug-986052-add-documentation-for-mozilla-uitour

[fix bug 986052] Add documentation for running Mozilla.UITour on Bedrock
Fix Bug 947992 - Request to Verify YouTube on Mozilla.org
Merge pull request #1829 from kyoshino/bug-947992-youtube-verification

Fix Bug 947992 - Request to Verify YouTube on Mozilla.org
Make channel-based download url to fix Bug 987330

Also remove major_version context variable in favor
of model method
Merge pull request #1822 from jgmize/relnotes-download-url

Make channel-based download url to fix Bug 987330
bug 973967 - Refresh Get Involved page

This removes the 15th Anniversary slideshow.
fix bug 984602 - update MDN logo