Add http proxy support

[Goblenus]

Now you can use http proxy :)

[Fitblip]

Ooh nice! Thanks for the PR, and great idea :)

I'm going to propose a counter-pr to yours that actually structures this a bit differently to essentially expose any of the WebsocketApp.run_forever method's arguments (by passing around kwargs instead of explicit arguments). The documentation/consumption should be the same and just allows one to override some other features (like the origin, or ssl configuration, etc).

[Goblenus]

Not sure, that this a best way to add note about kwargs.

[Fitblip]

Nice, maybe we should link to the function itself so they can see what options are available easily?

https://github.com/websocket-client/websocket-client/blob/87861f951d1a65ed5d9080f7aaaf44310f376c56/websocket/_app.py#L169-L192

Cheers :)

[Goblenus]

I thought about that, and this is not good idea, because the function location may be changed and our url will be useless. But this is the best way to tell why and what for we use kwargs.

[Fitblip]

That URL is actually a permalink to that function args/docs at that specific commit, which of course means it won't be updated automatically, but it will be correct for some definition of correct which I think will suffice for our needs.

The github permalink thing is also just another one of those neat github things that's not obvious, so in case you were wondering where I got it:

[Goblenus]

Wow...I didn't know about that, thanks. Can you add url and merge by yourself?

[Fitblip]

Sure! Just wanted to make sure you were cool with it :)

Thanks again for the PR!