url:SetQuery(query$[, flags])
query$.
The query part will also get spaces converted to pluses when asked to URL encode
on get with the #CURLU_URLENCODE bit. If used together with the #CURLU_APPENDQUERY
bit, the provided part is appended on the end of the existing query. The question
mark in the URL is not part of the actual query contents.
You can also pass Nil to unset the query in the URL handle.
The optional flags parameter can be a combination of flags as described in
the documentation of the hurl.URL() function. See hurl.URL for details.