new :query option appends url query string to requests with any http method (GET, POST, PUT, ...)

It wasn't possible to add an url query string to other than GET/HEAD requests.

This update preserves original `:payload` option (works same as before), additionally there is a new option `:query` which adds an url query string to requests with any http method.

Because now `:payload` and `:query` options has the same meaning for GET/HEAD requests, the `:query` option has a precedence before `:payload`.

+ fixes Query.new docs (:delegator -> :action)