Add ABC supporters to index.html, subfolder 'sponsors' in img, sponsor logos (#125)

• initial add of supporter logos and index.html code

• initial add of supporter logos and index.html code

fixed img src tag for top level sponsor image

• added new logo fullstackcash.png, added colored box around supporters

section

• Jason patch, fullstack re-added. Let's get this done and make it better next time.

• fixed unclosed div