Log JSON payload if a JSON parsing error occured

[LEQADA]

Right now if this line fails
https://github.com/commercetools/commercetools-adyen-integration/blob/a6959d906ab6cc5050b872daefb6de40f88cb071/notification/src/api/notification/notification.controller.js#L17

we will log it like this:

err: {
 message:  "Unexpected number in JSON at position 652"    
 name:  "SyntaxError"    
 stack:  "SyntaxError: Unexpected number in JSON at position 652
  at JSON.parse (<anonymous>)
  at handleNotification (/app/src/api/notification/notification.controller.js:16:38)
  at process._tickCallback (internal/process/next_tick.js:68:7)"    
}

It's impossible to identify what was exactly wrong with the payload that it failed to parse.
We should catch the JSON parsing separately and in this case log the payload too.