remove invalid statements

Author: wildone

.travis.yml

@@ -17,24 +17,18 @@ before_install:
   - if [[ $TRAVIS_BRANCH != "master" && $SONAR_ENABLED == "true" ]]; then mvn sonar:sonar "-Dsonar.branch.name=${TRAVIS_BRANCH}" "-Dsonar.branch.target=master" "-Dsonar.host.url=${SONAR_URL}" "-Dsonar.login=${SONAR_TOKEN}" "-Dsonar.organization=${SONAR_ORGANISATION}"; fi
 
 install:
-  - mvn --settings default.xml install -DskipTests=true -Dgpg.skip -Dmaven.javadoc.skip=true -B -V
-  on:
-    branch: master
+  - if [[ $TRAVIS_BRANCH != "master" ]]; then mvn --settings default.xml install -DskipTests=true -Dgpg.skip -Dmaven.javadoc.skip=true -B -V; fi
 
 ## Build and release to maven central
 script:
   - if [[ $TRAVIS_BRANCH == "master" ]]; then mvn clean deploy --settings default.xml -DskipTests=true -B -U -Prelease; fi
-  on:
-    branch: master
 
 ## Get the project version
 before_deploy:
   - mvn help:evaluate -N -Dexpression=project.version|grep -v '\['
   - export project_version=$(mvn help:evaluate -N -Dexpression=project.version|grep -v '\[')
   - export TRAVIS_TAG=$project_version
-  - git tag $TRAVIS_TAG
-  on:
-    branch: master
+  - if [[ $TRAVIS_BRANCH != "master" ]]; then git tag $TRAVIS_TAG; fi
 
 ## Create release in GitHub
 deploy: