Add schema

README.md

@@ -1,2 +1,13 @@
 # OPENAPI Parser
-Basic library to extract schema structures from OpenAPI 3 documents.
+Basic library to extract schema structures from OpenAPI 3 documents.
+
+This crate can be used as a standalone binary:
+```bash
+cargo install openapi-parser
+```
+
+
+Create a tree graph for a schema:
+```bash
+openapi-parser -f openapi.yaml -s MySchema graph | dot -Tpng > dest.png
+```