Inability to remove twitter, ads, and cards

[jpegburch]

These current options within settings.yml are backed up with multiple steps to produce them within the landscape. For example, when removing the twitter options within settings.yml, the file tweetbutton.js files a failure at text: settings.twitter.text, and cannot run. When attempting to simply just remove this one line, the code fails in a different spot, and similarly fails when trying to just remove the whole file. A similar story follows for the other options, suggesting that three options are in the code in multiple places. It might be easier to just add our own version of each instead of removing each of them, but open to suggestion.

[ljanicke]

Changed the CNCF ad to be a NREL logo linked to the NREL website.

[shankari]

[shankari]

Removed the ad; not sure about twitter et al