Promote CID related code to core (out of amp-analytics)

[lannka]

Motivation:
Many extensions need CID hence depend on amp-analyitcs. We could remove the dependencies once get CID promoted to core.

• amp-user-notification
• amp-ad
• amp-access
• Any place needs CLIENT_ID in URL substitution

And, starting recently <amp-analytics> is blocked by ad blocker: #4896 .

Work to be done
This would need to move the following code to core, the cons is increased core size, an estimate is listed below:

File to promote	Raw file size	Minified size
cid-impl.js	12k	3.7k
crypto-impl.js	3.6k	2.0k
closure/sha384.js	9.2k	9.2k

The real size after closure complier should be smaller.
And we can late load the sha384.js lib as tracked here: #3888

[lannka]

One more PR needed: move CID code to core. After that, we should change READMEs of those extensions that previously dependent on amp-analytics to generate CID.

[lannka]

The remaining work is tracked as a Great First Issue here: #9713