Update EC v3 release notes - #4360

Changed pages include:

• index.html - view
• 404.html - view
• blog.html - view
• intro-kots.html - view
• intro-replicated.html - view
• search.html - view
• enterprise/auth-changing-passwords.html - view
• enterprise/cluster-management-add-nodes.html - view
• enterprise/delete-admin-console.html - view
• enterprise/image-registry-kurl.html - view

There are more changes not included in the list