Use icu for date and time localization (#934)

* Use icu for date and time localization

* Handle military time config in dialog

src/config.rs

@@ -3,7 +3,7 @@
 use std::{any::TypeId, num::NonZeroU16, path::PathBuf};
 
 use cosmic::{
-    cosmic_config::{self, cosmic_config_derive::CosmicConfigEntry, ConfigGet, CosmicConfigEntry},
+    cosmic_config::{self, cosmic_config_derive::CosmicConfigEntry, CosmicConfigEntry},
     iced::Subscription,
     theme, Application,
 };
@@ -205,7 +205,7 @@ pub struct TabConfig {
     pub show_hidden: bool,
     /// Icon zoom
     pub icon_sizes: IconSizes,
-    #[serde(skip, default = "military_time_enabled")]
+    #[serde(skip)]
     /// 24 hour clock; this is neither serialized nor deserialized because we use the user's global
     /// preference rather than save it
     pub military_time: bool,
@@ -220,27 +220,12 @@ impl Default for TabConfig {
             folders_first: true,
             show_hidden: false,
             icon_sizes: IconSizes::default(),
-            military_time: military_time_enabled(),
+            military_time: false,
             single_click: false,
         }
     }
 }
 
-/// Return whether the user enabled military time via the Time applet.
-fn military_time_enabled() -> bool {
-    // Borrowed from COSMIC Greeter
-    match cosmic_config::Config::new("com.system76.CosmicAppletTime", 1) {
-        Ok(config_handler) => config_handler.get("military_time").unwrap_or_default(),
-        Err(err) => {
-            log::error!(
-                "failed to create CosmicAppletTime config handler: {:?}",
-                err
-            );
-            false
-        }
-    }
-}
-
 #[derive(Clone, Copy, Debug, Eq, PartialEq, CosmicConfigEntry, Deserialize, Serialize)]
 #[serde(default)]
 pub struct IconSizes {
@@ -270,3 +255,11 @@ impl IconSizes {
         percent!(self.grid, ICON_SIZE_GRID) as _
     }
 }
+
+pub const TIME_CONFIG_ID: &str = "com.system76.CosmicAppletTime";
+
+#[derive(Debug, Default, Clone, CosmicConfigEntry, PartialEq, Eq)]
+#[version = 1]
+pub struct TimeConfig {
+    pub military_time: bool,
+}