Prevent leaving breadcrumbs when log is below a certain level

[bonroyage]

Goal

Currently anything that is below the notify level gets added as a breadcrumb on a log that is notifiable. In one of our apps we use debug logs extensively during development, but don't expect these to be logged on a production environment at all, because they can contain sensitive data.

The intention of the breadcrumbLevel is to set a minimum level of a log message for it to be added as a breadcrumb.

Design

I have kept it in line with the existing notifyLevel property and setNotifyLevel method. The default for the breadcrumbLevel is DEBUG. Unless explicitly changed, functionally nothing with change for existing users.

Testing

Existing test was modified to set the minimum breadcrumb level to INFO, causing the DEBUG log that was there not to trigger the leaveBreadcrumb method.

[clr182]

Hi @bonroyage
Thank you for opening this PR. I've passed it on to our engineers for further consideration. We will let you know more once we have an update.