* Direct avatar rendering
This adds new template helpers for avatar rendering which output image
elements with direct links to avatars which makes them cacheable by the
browsers.
This should be a major performance improvment for pages with many avatars.
* fix avatars of other user's profile pages
* fix top border on user avatar name
* uncircle avatars
* remove old incomplete avatar selector
* use title attribute for name and add it back on blame
* minor refactor
* tweak comments
* fix url path join and adjust test to new result
* dedupe functions
* Add class to page content to unify top margin
Previously pages would individually set this margin but some didn't so
content would stick to the header without any space. Resolve this by
adding a new class that is added on all pages. The only place where we
remove this margin again is on the pages with menu or wrapper in the
header.
* fix admin notices
* fix team pages
* fix loading segment on gitgraph for arc-green
* fix last missing case
Co-authored-by: techknowlogick <techknowlogick@gitea.io>