Make alignment a widget property

core/src/widget/data.rs

@@ -1,10 +1,11 @@
-use crate::{SizeRules, Widget};
+use crate::{RegionAlign, SizeRules, Widget};
 
 pub struct WidgetData {
     pub widget: Box<dyn Widget>,
     pub label: String,
     pub(super) region_node: bool,
     pub(super) size: SizeRules,
+    pub(super) align: RegionAlign,
     /// dynamic borrow checking
     pub borrowed: bool,
 }
@@ -20,6 +21,7 @@ impl WidgetData {
             label,
             region_node: false,
             size: SizeRules::default(),
+            align: RegionAlign::default(),
             borrowed: false,
         }
     }