Add more icons for products and solutions

[rdebeasi]

Sounds good! Could you please:

• Consolidate #33, #34, #35, and #36 into one "Add more icons" issue
• Add descriptions and official logos for each icon that you'd like to see added.

Thank you!

[oybed]

This PR has been converted to a "catch-all" for adding more content:

• Spock Framework (testing tool)
• Splunk (monitoring and logging)
• Container Engines (CRI-O, RKT)
• AWS GovCloud