fixed travis build for pull requests

.travis.yml

 language: java
 before_install: "git clone -b travis `git config --get remote.origin.url` target/travis"
-script: "mvn deploy --settings target/travis/settings.xml"
+script: "[ ${TRAVIS_PULL_REQUEST} = 'false' ] && mvn clean deploy --settings target/travis/settings.xml || mvn clean verify --settings target/travis/settings.xml"
 
 # whitelist
 branches: