Release Grails 3.1.0.M3

Author: graemerocher

build.gradle

@@ -21,7 +21,7 @@ apply plugin: 'idea'
 ext {
     bintrayPublish = false
     // Sets release version
-    grailsVersion = '3.1.0.BUILD-SNAPSHOT'
+    grailsVersion = '3.1.0.M3'
     isBuildSnapshot = grailsVersion.endsWith(".BUILD-SNAPSHOT")
     isTravisBuild = System.getenv().get("TRAVIS") == 'true'