v0.1.13: Convert `ErrorEvent`

Trying to use `ErrorEvent` in `postMessage` result in a non-clonable object error.

Log the original error to the console if posting the error fails.

v0.1.12: Webpack build UMD.

Also compile as ESM using tsc.
Closes #1

v0.1.11

Throw a Cancelled instead of a normal Error when handler is removed.

v0.1.10

Fix passing the error for a promise reject.

v0.1.9: Cancel outstanding calls when removing event handler.

Change typing to accept web worker as child.

v0.1.8

Fix returning the result of a promise.

v0.1.7

Fix exports in package.json

v0.1.6: Added option to remove event handler.

Rename 'connect.ts' to 'sender.ts'

v0.1.5: Clean up after resolving call.

Test timeout

v0.1.4

Configure two entries in webpack: sender and listener