Switch from jasmine to mocha + expect + lolex

Much of this transformation has been done automatically:
 * add expect import to each file
 * replace `not.to` with `toNot`
 * replace `to[Not]Be{Undefined,Null}` with equivalents
 * replace `jasmine.createSpy(...)` with `except.createSpy`, and `andCallFake`
   with `andCall`

Also:
 * replace `jasmine.createSpyObj` with manual alternatives
 * replace `jasmine.Clock` with `lolex`

spec/unit/pushprocessor.spec.js

@@ -3,6 +3,8 @@ import 'source-map-support/register';
 const PushProcessor = require("../../lib/pushprocessor");
 const utils = require("../test-utils");
 
+import expect from 'expect';
+
 describe('NotificationService', function() {
     const testUserId = "@ali:matrix.org";
     const testDisplayName = "Alice M";