I'm pretty "new" when it comes to this stuff, so bear with me.
I entered the command vi ~/.zcash/zcash.conf so I could create the Zcash.conf file, but I screwed something up. Then, apparently, I further complicated the problem by "x-ing" out of the terminal instead of quiting with the correct command.
At this point, I just want to start over (create the .conf and enter testnet details) but whenever I enter vi ~/.zcash/zcash.conf I get the error below. I'm not sure how to fix this problem. I'm guessing somebody here can fix it in 5 minutes, so it makes more sense for me to break down and ask, rather than spend another couple hours trying to figure it out.