Replaces `[image]` tags in libuv manual page with a textual representation of the graphical image. In addition added alternative-text for graphical deliverables. Fixes: https://github.com/libuv/libuv/issues/4708
PR-URL: https://github.com/libuv/libuv/pull/886 Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
PR-URL: https://github.com/libuv/libuv/pull/819 Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
