Refer to popovers instead of tooltips.
Merge pull request #12080 from Quy/master

Refer to popovers instead of tooltips.
Update source code download structure
Merge pull request #12081 from Quy/master

Update source code download structure
de-emphasize /docs/assets and docs HTML now that they're outside of the root dir
flip order so sentence reads better
Replace lingering page.url instance with site.baseurl

Refs #12083 & #12037