Hi,
this PR adds a function to parse the URI query into a HashMap to allow easier retrieval of the values plus some convenience functions. Finally, it is quite easy to just do:

let my_query_value = match uri.query_param_first("foo") {
   Some(value) => value,
   None => "my-default-value"
}

The code is provided as is and I hope it helps someone. Please be aware that I am relatively new to Rust and hope that the added tests ensure that I did not screw up totally ;-)
Best,
Manuel