Remove whitespaces from end of line

These whitespaces have been accidentally committed in
c8af80e.

Author: stefanbirkner

.travis.yml

@@ -3,7 +3,7 @@ install:
   # Download dependencies with JDK 8 because Maven Central supports
   # TLS 1.2 only but OpenJDK 6 does not.
   - export ORIGINAL_JAVA_HOME=$JAVA_HOME
-  - jdk_switcher use oraclejdk8     
+  - jdk_switcher use oraclejdk8
   - ./mvnw test -DskipTests
   # Delete all files created with JDK 8
   - ./mvnw clean