Add 'nothing' matcher and tests

spec/core/matchers/nothingSpec.js

@@ -0,0 +1,8 @@
+describe('nothing', function() {
+  it('should pass', function() {
+    var matcher = jasmineUnderTest.matchers.nothing(),
+      result = matcher.compare();
+
+    expect(result.pass).toBe(true);
+  });
+});

src/core/matchers/nothing.js

@@ -0,0 +1,20 @@
+getJasmineRequireObj().nothing = function() {
+  /**
+   * {@link expect} nothing explicitly.
+   * @function
+   * @name matchers#nothing
+   * @example
+   * expect().nothing();
+   */
+  function nothing() {
+    return {
+      compare: function() {
+        return {
+          pass: true
+        };
+      }
+    };
+  }
+
+  return nothing;
+};

src/core/matchers/requireMatchers.js

@@ -1,5 +1,6 @@
 getJasmineRequireObj().requireMatchers = function(jRequire, j$) {
   var availableMatchers = [
+      'nothing',
       'toBe',
       'toBeCloseTo',
       'toBeDefined',