WIP(test): unify mocha/jasmine/jest test

[JiaLiPassion]

let zone-testing can handle mocha/jasmine/jest test cases without difference (almost).

1. when load zone-testing, will auto check if using jasmine or mocha, and zone-testing will load patch accordingly.

2. Expose async/fakeAsync/tick/flush/discardPeriodicTasks/flushMicrotasks/resetFakeAsyncZone APIs to global, so user can use those APIs directly.

And add clearAllMacrotasks, flushAndDiscardPeriodicTasks helper methods.

3. add jasmine/jest mapping in Mocha patch, so user can write case in jasmine style and API and can still use Mocha as runner to test.

• support jasmine expect
• support jasmine spy
• support jasmine clock
• add BDD mapping such as (beforeAll/afterAll/fdescribe/fit/pending...)
• support jest expect
• support jest mockFn
• suport jest TimerMock

4. Refactoringtest/build/doc folder, current there are too many test/karma/ci file in root folder or in test folder, so re-organize the folder.

5. Add zone-testing.typing.d.ts, https://github.com/JiaLiPassion/zone.js/blob/26a2b611aa07e71d4af734f620f29a802b61ebc3/lib/testing/zone-testing.typing.ts, it defines all supported jasmine/mocha/jest APIs.

User can still use jasmine or mocha or jest type definition if they don't want to use this zone-testing mix.

Because this zone-testing.typing.d.ts will have conflict (duplicate declaration) with jasmine or mocha or jest type definition, so maybe we should publish this zone-testing.typing.d.ts to @types repo?