Add docs page links to user guide

[exalate-issue-sync]

“Hi Hannah! I've been having some discussions with marketing about our documentation website, and we were wondering whether you think it's a good idea to move some of the links from [this page|https://docs.h2o.ai/h2o-3/index.html] to the landing page (or some other page) of the H2O user guide

This would ultimately let us reduce the number of clicks to get to our docs since we could eliminate the need for separate pages for each product”

→ Recent Changes can link directly to the Release Notes

→ Create a new tab in User Guide called and structure similarly to the current docs index page (can pull resources from algorithms since they're in the algo section above)

[h2o-ops]

JIRA Issue Details

Jira Issue: PUBDEV-8631
Assignee: hannah.tillman
Reporter: hannah.tillman
State: Resolved
Fix Version: 3.36.1.1
Attachments: N/A
Development PRs: Available

[h2o-ops]

Linked PRs from JIRA

#6144