refactor project structure (start of redoing atomic branch without atomics)

src/widget/position/mod.rs

@@ -0,0 +1,19 @@
+mod align;
+mod layer;
+mod max_size;
+mod offset;
+mod pad;
+mod scroll;
+mod sized;
+mod span;
+mod stack;
+
+pub use align::*;
+pub use layer::*;
+pub use max_size::*;
+pub use offset::*;
+pub use pad::*;
+pub use scroll::*;
+pub use sized::*;
+pub use span::*;
+pub use stack::*;