refactor(message): rename dc_msg to message

src/dc_mimefactory.rs

@@ -17,10 +17,10 @@ use crate::contact::*;
 use crate::context::{dc_get_version_str, Context};
 use crate::dc_e2ee::*;
 use crate::dc_location::*;
-use crate::dc_msg::*;
 use crate::dc_strencode::*;
 use crate::dc_tools::*;
 use crate::error::Error;
+use crate::message::*;
 use crate::param::*;
 use crate::stock::StockMessage;
 use crate::types::*;