There were no changes to httpGet, but it appears that you changed the file in github. I ran that url through postman and it is returning "text/plain" for the content type, so that is why it is not being parsed into an object and instead is just giving you a String back.
I found that helpful. Like a lot of syntax problems, jsonlint doesn't come out and say "hey, missing comma" but it does say good/bad quite well. And sometimes that's half the battle !!
The site says you can enter a URL and it'll scrape it for JSON but it doesn't follow links. Browsing to your JSON and then entering THAT URL yields the warm: Valid JSON
I edit with Atom text editor and it does a nice job of pointing out my mistakes. Nice when working on an RPi image file too. You can see, edit and delete the hidden files.