Git: Added v4.0 i8n json files to .gitignore file.
Merge pull request #5446 from EricDunsworth/v3.1-git-gitignore

Git: Added v4.0 i8n json files to .gitignore file.
Merge pull request #5445 from EricDunsworth/v3.1-broken-link-fixes

Demos/Documentation: Fixed and corrected various broken+missing links.
Demos: Removed SSI variant's demos landing page due to decommissioned links.
Related to wet-boew/wet-boew-ssi#64.