I always pass catch_exceptions=False for all my test suites.
It would be convenient to configure this value once for all in CLIRunner for example.

For example, we could add a CLIRunner.catch_exceptions parameter, and make invoke use that value if not directly passed in parameter of invoke. Then I would just have to put the runner in a pytest fixture and that would do the thing for me.

If that is OK, I can open a PR for this.

What do you think?