Return false to georerferencer if any exception

This fixes #1354

The code was already there in order to capture a very specific
ContentGuesserException. I modified it to capture and log any exception in the ContentGuesser.
I know the procedure to log the error is a bit controversial, but I
tested it and I'm open to discussion, if needed.

Note: this can be tested on staging. For instance, by changing its geocoding config and see that it actually can continue importing stuff and logs the problem to rollbar and to the importer log.