Add schema modeling guidance to use wildcard syntax instead of regex (#71)

* Add schema modeling guidance to use wildcard syntax instead of regex

* Update guidance to include included, excluded properties

Author: jack-berg

README.md

@@ -31,11 +31,12 @@ Allowable changes:
 - For major versions: All changes are permitted.
 - For minor versions: TBD
 
-## Naming guidelines
+## Schema Modeling Guidelines
 
-The following defines guidelines used to produce configuration schema:
+The following guidelines are used to model the configuration schema:
 
-1. To remove redundant information from the configuration file, prefixes for data produced by each of the providers
-will be removed from configuration options. For example, under the `meter_provider` configuration, metric readers will be
-identified by the word `readers` rather than by `metric_readers`. Similarly, the prefix `span_` will be dropped for tracer
-provider configuration, and `logrecord` for logger provider.
+* To remove redundant information from the configuration file, prefixes for data produced by each of the providers will be removed from configuration options. For example, under the `meter_provider` configuration, metric readers will be identified by the word `readers` rather than by `metric_readers`. Similarly, the prefix `span_` will be dropped for tracer provider configuration, and `logrecord` for logger provider.
+* Use wildcard `*` (match any number of any character, including none) and `?` (match any single character) instead of regex. If a single property with wildcards is likely to be insufficient, accept `included` and `excluded` properties, each with an array of strings with wildcard entries. The wildcard entries should be joined with a logical OR. If `included` is not specified, assume that all entries are included. Apply `excluded` after applying `included`. Examples:
+  * Given `excluded: ["a*"]`: Match all except values starting with `a`.
+  * Given `included: ["a*", "b*"]`, `excluded: ["ab*"]`: Match any value starting with `a` or `b`, excluding values starting with `ab`.
+  * Given `included: ["a", "b"]`, `excluded: ["a"]`: Match values equal to `b`.