error handling - first run

[sscrawfo]

Just a couple of nits from my first attempt to use:
For some reason, the json parser didn't like a / at the end of my URLs, I needed to remove those.
The error message was non-descript.

Also, the code expects a /dashboards folder to exist. Easy fix, but the error also isn't obvious, probably
could just go ahead and create that if it's not there, or error out immediately.

Otherwise seems amazing, and exactly what I was considering building untils I found it.

[QuentinAmbard]

the /dashboards folder should be created by default if not existing with the last release