Make rake jasmine:ci run specs correctly.

- Will replace rake core_specs.
- Remove obsolete dependencies & files -- most of these were for build tasks we
  are no longer using. Notably, rspec and spec_helper were deleted.

spec/javascripts/core/TimerSpec.js

@@ -0,0 +1,13 @@
+describe("Timer", function() {
+  it("reports the time elapsed", function() {
+    var fakeNow = jasmine.createSpy('fake Date.now'),
+        timer = new j$.Timer({now: fakeNow});
+
+    fakeNow.and.returnValue(100);
+    timer.start();
+
+    fakeNow.and.returnValue(200);
+
+    expect(timer.elapsed()).toEqual(100);
+  });
+});