Update readme versions

Author: dinomite

README.md

@@ -1,4 +1,4 @@
-[![Kotlin](https://img.shields.io/badge/kotlin-1.3.x-blue.svg)](http://kotlinlang.org) [![CircleCI](https://circleci.com/gh/FasterXML/jackson-module-kotlin.svg?style=svg)](https://circleci.com/gh/FasterXML/jackson-module-kotlin) [![Kotlin Slack](https://img.shields.io/badge/chat-kotlin%20slack-orange.svg)](http://slack.kotlinlang.org/)
+[![Kotlin](https://img.shields.io/badge/kotlin-1.4.x-blue.svg)](http://kotlinlang.org) [![CircleCI](https://circleci.com/gh/FasterXML/jackson-module-kotlin.svg?style=svg)](https://circleci.com/gh/FasterXML/jackson-module-kotlin) [![Kotlin Slack](https://img.shields.io/badge/chat-kotlin%20slack-orange.svg)](http://slack.kotlinlang.org/)
 
 # Overview
 
@@ -10,11 +10,7 @@ and those with secondary constructors or static factories are also supported.
 
 # Status
 
-2.9.8+ Releases are compiled with Kotlin 1.3.x, other older releases are Kotlin 1.2.x.
-All should be compatible with current Kotlin if you also ensure the `kotlin-reflect`
-dependency is included with the same version number as stdlib.
-
-* release `2.12.0` (for Jackson `2.12.x`) [![CircleCI](https://circleci.com/gh/FasterXML/jackson-module-kotlin/tree/2.12.svg?style=svg)](https://circleci.com/gh/FasterXML/jackson-module-kotlin/tree/2.12)
+* release `2.12.3` (for Jackson `2.12.x`) [![CircleCI](https://circleci.com/gh/FasterXML/jackson-module-kotlin/tree/2.12.svg?style=svg)](https://circleci.com/gh/FasterXML/jackson-module-kotlin/tree/2.12)
 * release `2.11.4` (for Jackson `2.11.x`) [![CircleCI](https://circleci.com/gh/FasterXML/jackson-module-kotlin/tree/2.11.svg?style=svg)](https://circleci.com/gh/FasterXML/jackson-module-kotlin/tree/2.11)
 * release `2.10.5` (for Jackson `2.10.x`)
 * release `2.9.10` (for Jackson `2.9.x`)
@@ -31,7 +27,7 @@ Maven:
 <dependency>
     <groupId>com.fasterxml.jackson.module</groupId>
     <artifactId>jackson-module-kotlin</artifactId>
-    <version>2.12.0</version>
+    <version>2.12.3</version>
 </dependency>
 ```