Mockup of the new package os interface (incomplete and non-functioning)

core/os/os2/heap.odin

@@ -0,0 +1,21 @@
+package os2
+
+import "core:runtime"
+
+heap_allocator :: proc() -> runtime.Allocator {
+	return runtime.Allocator{
+		procedure = heap_allocator_proc,
+		data = nil,
+	};
+}
+
+
+heap_allocator_proc :: proc(allocator_data: rawptr, mode: runtime.Allocator_Mode,
+                            size, alignment: int,
+                            old_memory: rawptr, old_size: int, flags: u64 = 0, loc := #caller_location) -> rawptr {
+	return _heap_allocator_proc(allocator_data, mode, size, alignment, old_memory, old_size, flags, loc);
+}
+
+
+@(private)
+error_allocator := heap_allocator;