update readme

README.md

@@ -40,15 +40,15 @@ Spring Boot Admin provides the following features for registered applications:
 
 ## Getting Started
 
-[A quick guide](http://codecentric.github.io/spring-boot-admin/2.3.0/#getting-started) to get started can be found in our docs.
+[A quick guide](http://codecentric.github.io/spring-boot-admin/2.3.1/#getting-started) to get started can be found in our docs.
 
 There are introductory talks available on YouTube:
 
-<a href="https://youtu.be/Ql1Gnz4L_-c" target="_blank"><img src="https://i.ytimg.com/vi/Ql1Gnz4L_-c/maxresdefault.jpg" 
+<a href="https://youtu.be/Ql1Gnz4L_-c" target="_blank"><img src="https://i.ytimg.com/vi/Ql1Gnz4L_-c/maxresdefault.jpg"
 alt="Cloud Native Spring Boot® Admin by Johannes Edmeier @ Spring I/O 2019" width="240" height="135" border="10" /></a><br>
 **Cloud Native Spring Boot® Admin by Johannes Edmeier @ Spring I/O 2019**
 
-<a href="https://youtu.be/__zkypwjSMs" target="_blank"><img src="https://i.ytimg.com/vi/__zkypwjSMs/maxresdefault.jpg" 
+<a href="https://youtu.be/__zkypwjSMs" target="_blank"><img src="https://i.ytimg.com/vi/__zkypwjSMs/maxresdefault.jpg"
 alt="Monitoring Spring Boot® Applications with Spring Boot Admin @ Spring I/O 2018" width="240" height="135" border="10" /></a><br>
 **Monitoring Spring Boot® Applications with Spring Boot Admin @ Spring I/O 2018**
 
@@ -69,9 +69,9 @@ Having trouble with codecentric's Spring Boot Admin? We’d like to help!
  * Report bugs at http://github.com/codecentric/spring-boot-admin/issues.
 
 ## Reference Guide
-[Version 2.1.6](http://codecentric.github.io/spring-boot-admin/2.1.6/)
+[Version 2.3.1](http://codecentric.github.io/spring-boot-admin/2.3.1/)
 
-[Version 2.0.6](http://codecentric.github.io/spring-boot-admin/2.0.6/)
+[Version 2.2.4](http://codecentric.github.io/spring-boot-admin/2.2.4/)
 
 [Version 1.5.7](http://codecentric.github.io/spring-boot-admin/1.5.7/)