Prepare for release 0.4.0. (#283)

Author: joshafeinberg

gradle.properties

@@ -22,7 +22,7 @@ kotlin.code.style=official
 
 # POM
 GROUP = com.dropbox.affectedmoduledetector
-VERSION_NAME=0.4.0-SNAPSHOT
+VERSION_NAME=0.4.0
 
 POM_ARTIFACT_ID = affectedmoduledetector
 POM_NAME = Affected Module Detector