Implement crash handling / error reporting

Details on the idea can be found here: https://forum.blockstack.org/t/proposal-opt-in-error-reporting-for-the-browser/5890

Technical implementation should be a componentDidCatch handler on the top level app component to render when an uncaught error bubbles up. For error reporting, I’d suggest making a new browser-api.blockstack.org endpoint to send an error to https://sentry.io/for/node/ that strips out identifying information (e.g. IP address.)

[hstove]

Comment from the issue I’m about to close:

We want to prototype some kind of automatic exception tracking in the Browser. This will help us catch and diagnose issues without users having to reach out to us with a backtrace.

There are complications related to the Browser:

• There is sensitive data that absolutely must not be sent to exception tracking services. No function arguments should be included, ever.
• This should probably be opt-in
• We might want to only support this in the ‘beta’ version of the Browser

The work here will be to prototype something, make sure it fulfills the requirements, test it, and then potentially release.

[markmhx]

@hstove Sounds great, thanks for pushing this forward quickly 💪🏻