sessionId support

[flotwig]

AFAIK currently, there's no way to set a sessionId for a single message like:

{
	id: ...,
	method: '...',
	params: { ... },
	sessionId: '...'
}

Chrome is planning to start requiring a sessionId to target a page at some point in the future: https://bugs.chromium.org/p/chromium/issues/detail?id=991325

Additionally, setting a sessionId is important if you connect to the global websocket instead of a target-specific websocket.

So this is probably something that should be added.

A sendRaw function that allows manually setting the entire message object would be fine for my use case too and wouldn't require too much refactoring.

[Niek]

I switched to the chrome-debugging-client package since that properly supports sessionIDs.