Allow setting query params for HTTPRequest

[skazhy]

Allow setting queryparams explicitly via query_params in HTTPRequest constructor.

This makes things less error prone, as urlencoding is done automatically, via the already existing httputils.url_concat method.

[skazhy]

Current implementation breaks websocket module. Working on an improved version.

[bdarnell]

Why wouldn't you just call url_concat directly if you want this?

uri is a poor name for the new property since the difference between it and the existing url property has nothing to do with the difference between URIs and URLs. In general I prefer to avoid properties since they make it less obvious how many times a computation is done - in this case I'd just compute the concatenated string in the constructor.

I haven't tested but it looks like this would incorrectly re-apply the query parameters when following redirects.

[bdarnell]

Closing due to inactivity.