Refactor dbus commands and internal data structures

rog-client/examples/per-key-effect-2.rs

@@ -1,4 +1,7 @@
-use rog_client::{AuraDbusWriter, Key, KeyColourArray};
+use rog_client::{
+    core_dbus::AuraDbusWriter,
+    fancy::{Key, KeyColourArray},
+};
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut writer = AuraDbusWriter::new()?;