Change from "classic" TS 1.6 imports to the default resolution scheme.

- Use relative imports in place of most of our absolute ones.
- Add "private" ambient modules for modules that we need to import using
an absolute path (e.g. when app/.../test-something.ts needs to import
ui/styling/style-scope)

ui/builder/binding-builder.d.ts

@@ -0,0 +1,16 @@
+//@private
+declare module "ui/builder/binding-builder" {
+    export module bindingConstants {
+        export var sourceProperty: string;
+        export var targetProperty: string;
+        export var expression: string;
+        export var twoWay: string;
+        export var source: string;
+        export var bindingValueKey: string;
+        export var parentValueKey: string;
+        export var parentsValueKey: string;
+        export var newPropertyValueKey: string;
+    }
+
+    export function getBindingOptions(name: string, value: string): any;
+}