Editorial: Stylize strings as values.

[spectranaut]

This follows the convention set in ECMA-262 to format strings as literals (*"string*" instead of `"string"`, see PR: tc39/ecma262#1733) and closes #54.

There is also one commit that adds a link in 5. Notational Conventions to ECMA-262.

While reviewing, consider the following conventions from ECMA-262 that I'm not positive apply here:

• Tilde for spec-interal values: I couldn't find an example of a spec internal value in ECMA-402 that is not also a string specified somewhere else, such as the IANA Time Zone Database or Unicode. Because the string is not an internal arbitrary value it doesn't seem like we should use ~.
• Notation for code points: I don't have an opinion on whether we should stylize characters the way ECMA-262 now stylizing code points, I'm curious if others do.

[rkirsling]

Woot! I'm so jealous that 402 is a multi-file spec. 😄

[rkirsling]

The only concern I see is that we may wish to change cases like *"ß"* (U+00DF) to `ß` (U+00DF) throughout this file, in alignment with, say, Note 4 of 21.2.2.8.2 in 262.

I don't have a strong opinion on this though, particularly since we're referring to these as "characters". (@jmdyck, what do you think?)

[jmdyck]

It seems to me that it's incorrect for the preceding para to talk about ES String values as if they consist of Unicode code points.

[leobalter]

I believe this can be done through a separate patch if necessary.