fix(web): improve `console.error()` reporting

The back story:

Currently Keyman for Android reports errors sent to the console via
`console.error()` into Sentry but sentry-manager itself does not. This
means that Keyman for iPhone and iPad and other users of sentry-manager
do not report these errors. Many of these errors are important.

What's worse is that Keyman for Android's error reporting here (via the
`sendKMWError()` function in Keyman Engine for Android) does not capture
stack traces, and so many of the errors we get do not have enough
information to resolve them.

Furthermore, by having `sendKMWError()` in Keyman for Android, we
capture exceptions and other program errors twice -- once on the web
side, and once on the Java side -- this adds noise to our error
reporting. Sentry also tends to lump many unrelated `sendKMWError()`
events together, so tracking resolution to the errors is painful.

The fix:

This adds a patch to sentry-manager to capture `console.error()` and
`console.warning()` events...