Distinguish languages and scripts clearly

[lianghai]

It seems currently in the doc, all discussions are by default based on languages, especially Hindi. However, as a doc of layout requirements, most issues are actually script-related and language-independent.

I suppose it'd better if:

• Languages an scripts are distinguished clearly. Even for words like "Gujarati" should be clarified if "the Gujarati language" of "the Gujarati script" is being talked in a certain piece of text if it's unclear from the context.

• Scripts should be discussed by default. Languages should be discussed only when there're language-dependent issues.