Rollbar: Investigate RoutingError exceptions and possibility ignore them

[murny]

99% of our rollbar exceptions right now are ActionController::RoutingError exceptions (e.g 404/not found requests).

These exceptions could happen for a number of reasons, like users entering the wrong URL by mistake or perhaps nefarious reasons (e.g. we are getting traffic to /wp-login). But sometimes they can happen for legit reasons, like we have a bad link in our application, or we are telling uses to download an asset that doesn't exist.

We should first investigate some of the most common ActionController::RoutingError exceptions and see if we can fix a few of them.

But ultimately we may want to just ignore these errors in Rollbar like we did for Jupiter: https://github.com/ualbertalib/jupiter/blob/master/config/initializers/rollbar.rb#L34

Link to exceptions in Rollbar: https://app.rollbar.com/a/ualbertalib/fix/item/library-cms/7

[murny]

#523 has been merged which is ignoring these errors in staging/production now.

But leaving this open as we should troubleshoot and fix some of these errors that are occurring.

We got a good 24 hours of data to look at. This should let us fix some easy ones we saw (e.g: favicons for Safari/IOS (apple-touch-icon), etc)