Accept iteratable parameters for chat apis

[linmx0130]

As title.

   messages: &Vec<ChatMessage>,    
   params: &HashMap<String, Value>,

Are changed into

    messages: M,
    params: P,
  where
    P: IntoIterator<Item = (&'a String, &'a Value)>,
    M: IntoIterator<Item = &'b ChatMessage>,

So that we can support more data types as input. As a big change, bump the version of nah_chat to v0.2.0