Add json as a MIME.
Merge pull request #561 from jordandukart/7.x-LIB-37

Add json as a MIME.
Add a hidden next button at the top of the form so that it becomes the first button triggered if a user submits the form with the enter key.
Merge pull request #562 from matthewperry/7.x-LIB-38

Add a hidden next button at the top of the form so that it becomes the ...
Updated JS to ignore hidden next button when adding the spinner to the form so it does not add two.
Merge remote-tracking branch 'origin/7.x' into 7.x-LIB-38
Merge pull request #563 from matthewperry/7.x-LIB-38

7.x lib 38