add CHANGELOG.md. Set version to 0.5.4

Author: Patrick Jackson

CHANGELOG.md

@@ -0,0 +1,6 @@
+## Unreleased
+
+## [0.5.4] - 2020-08-16
+ - kotlin 1.4.0 final
+ - change test.yml to just run a build (currently no tests)
+ - update to redux-kotlin 0.5.5

gradle.properties

@@ -22,7 +22,7 @@ kotlin.code.style=official
 org.gradle.internal.publish.checksums.insecure=true
 
 GROUP=org.reduxkotlin
-VERSION_NAME=0.5.5
+VERSION_NAME=0.5.4
 
 POM_ARTIFACT_ID=reduxkotlin-thunk
 POM_DESCRIPTION=Redux thunmk implementation for Redux-Kotlin.  Mulitiplatform supported.