Deemphasize tag use

[laurencelundblade]

There's general agreement that tags are only in CMW because some early implementations use them. If we were writing the document today we would leave out section 3.2 and focus solely on content format and media type.

Please remove mention of tags in the abstract and introduction.

Please note that section 3.2 is not recommended practice.

[nedmsmith]

I disagree that there is general agreement. Given the choice implementers still prefer using a CBOR tag over the alternatives. The CMW draft doesn't explain why use of CBOR tags breaks something or why they are undesirable. The draft should take the position of highlighting the tradeoffs from using one vs. the other. All of them are legitimate forms of tagging content per IANA.