For review: Update to Character Model for the World Wide Web: String Matching

The Editor’s Draft of the Working Group Note “Character Model: String 
Matching <https://w3c.github.io/charmod-norm/>” is out for wide review. 
We are looking for comments by *Wednesday, 21 October*.

The Character Model series of documents contains background material, 
best practices, and recommendations for specification authors, 
implementers, and content authors related to the use of character 
encodings and Unicode on the Web. The “String Matching” document deals 
with specifying content restrictions and the matching of identifiers in 
protocols and document formats for W3C specifications.

The new revision adds two new terminology definitions 
<https://w3c.github.io/charmod-norm/#dfn-user-facing-identifier> 
(“application internal identifiers”, “user-facing identifiers”) and a 
new section targeted to specification authors on “Specifying Content 
Restrictions 
<https://w3c.github.io/charmod-norm/#specifying-content-restrictions>” 
(Section 3.1). The Working Group would like comments about these 
specific changes; comments about other aspects of the document are also 
welcome.

Please send any comments as github issues 
<https://github.com/w3c/charmod-norm/issues>.