ReadME file updated

Author: rajeshkawali

README.md

@@ -1,2 +1,17 @@
 # Springboot-lombok-custom-validation-exception
 This project will show how to use lombok, custom-validation, exception handling
+
+### Lombok
+Explained how to use lombok features.
+
+### Custom Annotation
+Created custom annotation for field validation.
+
+### Custom Exception Handling
+How to handle exception by creating custom exception class, @ExceptionHandler and class level annotation @RestControllerAdvice.
+
+### Model Mapper and BeanUtil
+How to convert from entity to dto and vice versa.
+
+### H2 Database
+Used In memory H2 Database