feat(package): upgrade to ng v2.3+ (#574)

scripts/matchers.ts

@@ -0,0 +1,21 @@
+// tslint:disable
+/**
+ * @copyright Angular ng-bootstrap team
+ */
+beforeEach(() => {
+  jasmine.addMatchers({
+    toHaveCssClass(/*util, customEqualityTests*/) {
+      return {compare: buildError(false), negativeCompare: buildError(true)};
+
+      function buildError(isNot) {
+        return function (actual, className) {
+          const orNot = isNot ? 'not ' : '';
+          return {
+            pass: actual.classList.contains(className) === !isNot,
+            message: `Expected ${actual.outerHTML} ${orNot} to contain the CSS class "${className}"`
+          };
+        };
+      }
+    }
+  });
+});