jsdom integration

[awto]

The biggest part of debugging front-end application is debugging event handlers. Browsers expect the handlers to be executed synchronously but in the breakpoint, the debugger releases the thread, thus if there is something like event.stopPropagation after the breakpoint the propagation won't be stopped.

To avoid implementing all the standard propagations algorithms we can utilize jsdom where these are already implemented. This won't solve default actions problem still though (due to security restriction browsers don't give access to this functionality to scripts).

However, this would resolve target.dispatchEvent calls.