refactor: move most of the horrible add_module macro content into proper functions

src/modules/sysinfo.rs

@@ -22,7 +22,7 @@ pub struct SysInfoModule {
     interval: Interval,
 
     #[serde(flatten)]
-    pub common: CommonConfig,
+    pub common: Option<CommonConfig>,
 }
 
 #[derive(Debug, Deserialize, Copy, Clone)]
@@ -116,6 +116,10 @@ impl Module<gtk::Box> for SysInfoModule {
     type SendMessage = HashMap<String, String>;
     type ReceiveMessage = ();
 
+    fn name() -> &'static str {
+        "sysinfo"
+    }
+
     fn spawn_controller(
         &self,
         _info: &ModuleInfo,