Make local.properties optional.

.travis.yml

@@ -3,9 +3,6 @@ language: java
 jdk:
   - oraclejdk8
 
-before_install:
-  - touch local.properties
-
 install: true
 
 script: exec ./kobaltw assemble test

gradle/publishing.gradle

@@ -38,7 +38,9 @@ publishing {
 task install(dependsOn: publishToMavenLocal)
 
 Properties properties = new Properties()
-properties.load(project.rootProject.file('local.properties').newDataInputStream())
+if (new File('local.properties').exists()) {
+    properties.load(project.rootProject.file('local.properties').newDataInputStream())
+}
 
 bintray {
     user = properties.getProperty("bintray.user")