Update README.md

Author: Igor Chepurnoy

README.md

@@ -6,7 +6,7 @@
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-Yii2-rbac provides a web interface for advanced access control and includes following features:
+Yii2-RBAC provides a web interface for advanced access control and includes following features:
 
 - Allows CRUD operations for roles, permissions, rules
 - Allows to assign multiple roles or permissions to the user