Support headers and query strings in HTTP::WebSocket

[adamtrilling]

HTTP::WebSocket doesn't support query strings or headers. I need it to do so for a project that I'd like to use Crystal for, so I'd like to take a crack at making it work. For query strings, the solution in #3234 should work. For headers, I'm envisioning adding a headers parameter to HTTP::WebSocket.new(), like:

def self.new(uri : URI | String, headers : HTTP::Headers? = nil)

and

def self.new(host : String, path : String, port = nil, tls = false, headers : HTTP::Headers? = nil)

Then I will handle the parameter in the constructors for HTTP::WebSocket::Protocol. What do y'all think?

[sdogruyol]

Now that we have #4227 merged, can we close this?