Fix bug in JSON output

[bestchai]

When working with Kartik on a use of Texada, it was revealed that I had introduced some bug in the JSON output. This should be fixed.

Update: problem is that we were using Kartik's unprocessed logs where event names can have double quotes inside them. The fix would probably be to make sure to escape double quotes inside event names. The bad event is

#!c++

elemFind : css selector : div.content > img[style*="opacity: 1"]

[Issue created by carolemieux: 2015-11-24]

[Comment created by bestchai: 2015-11-24]
In case you don't get to this soon, can you document the bug -- i.e., give input that leads to bad JSON output?